A
Glossary of Photographic Terms compiled by Christopher
John Ball:
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Aberration
(1) Something that prevents light from being brought into sharp focus.
(2) Lens flaw - the inability of a lens to reproduce an accurate,
focused, sharp image. Aberration in simple lenses is sub-categorized
into seven types:
• Astigmatism - lines in some directions are focused less sharply
than lines in other directions,
• Chromatic aberration or Axial chromatic aberration - different
wavelengths of light coming into focus in front of and behind the
film plane, resulting in points of light exhibiting a rainbow-like
halo and reduction in sharpness,
• Coma - the image of a point source of light cannot be brought
into focus, but has instead a comet shape,
• Curvilinear distortion - distortion consisting of curved lines,
• Field curvature - the image is incorrectly curved,
• Lateral chromatic aberration also known as Transverse chromatic
aberration - variation in the magnification at the sides of a lens
(this aberration type used to be termed “lateral colour”),
• Spherical aberration - variation in focal length of a lens
from centre to edge due to its spherical shape - generally all parts
of the image, including its centre.
The effects of lens aberration usually increase with increases in
aperture or in angle of field.
Abrasion
Marks
On the emulsion surface of the film are caused by scratching. It can
be due to traces of dirt trapped between layers of film as it is wound
on the spool, dirt in the film holder or grit on the pressure plate
Absolute
White
In theory, a material that perfectly reflects all light energy at
every visible wavelength. In practice, a solid white known spectral
data used as the " reference white " for all measurements
of absolute reflectance.
Absorption
Occurs when light is partially or completely absorbed by a surface,
converting its energy to heat.
Abstract
In the photographic sense, an image that is conceived apart from concrete
reality, generally emphasizing lines, colours and geometrical forms,
and their relationship to one another.
Accelerator
Is a chemical added to a developer solution to speed up the slow working
action of the reducing agents in the solution.
Accessory
An add-on to a computer; a peripheral like a mouse or a printer. Something
not central to the computer's operation.
Accessory
Shoe
Is a metal or plastic fitting on the top of the camera which support
accessories such as viewfinder, rangefinder, or flash gun. The term
" hot shoe " is sometimes uses as an alternative to accessory
shoe.
Acetate
Base
Non-inflammable base support for film emulsions which replaces the
highly inflammable cellulose nitrate base.
Acetic
Acid
Is a chemical used for stop bath which stops the action of the alkaline
developer.
Acetone
A solvent chemical used in certain processing solutions that contain
materials not normally soluble in water.
Achromatic
Is a lens system that has been corrected for chromatic aberration.
Acid
Hardener
Is a substance used in acid fixer to help harden the gelatine of the
emulsion.
Acutance
A measure of the sharpness with which the film can produce the edge
of an object.
Adapter
Ring
Is a circular mount, available in several sizes enabling accessories
such as filters to be used with lenses of different diameters.
Additive
Palette
This is a set of colours selected to represent, as closely as possible,
the colours in the original source image.
Additive
Primary Colours
Red, Green, Blue; The 3 colours used to create all other colours when
direct, or transmitted light is used .They are called additive primaries,
because when those are superimposed they produce white.
Adjustable
Camera
A camera with manually adjustable settings for distance, lens openings,
and shutter speeds.
Adjustable-Focus
Lens
A lens that has adjustable distance settings, as apposed to fixed
focus. These lenses can be manual or auto focus
Advanced
Photo System (APS)
A new standard in consumer photography developed by Kodak and four
other System Developing Companies - Canon, Fuji, Minolta and Nikon
- based on a new film format and photo-finishing technologies.
Advantix
Kodak brand name that identifies the Advanced Photo System.
Agitation
Keeping photographic chemicals (developer, stop bath, or fixer) in
a gentle, uniform motion whilst processing film or paper. Agitation
helps to speed and achieve even development and prevent spotting or
staining.
Air
Bubbles
Clear areas, usually circular, on film, produced by bubbles of air
trapped on the film during development. They are caused by insufficient
agitation while developing the film.
Alkalinity
Denotes the degree of alkali in a solution, measured in pH values.
All values above pH 7 are alkaline.
Ambient Light
The name sometimes given to available light that completely surrounds
a subject, sometimes called 'wrap around'. Light already existing
in an indoor or outdoor setting that is not caused by any illumination
supplied by the photographer.
Amidol
Soluble reducing agent which works at low pH values
Anastigmatic
Is a compound lens which has been corrected for the lens aberration
" astigmatism ".
Angle
of incidence
When light strikes a surface it forms an angle with an imaginary line
known as the : normal, which is perpendicular to the surface. The
angle created between the incident ray and the normal is referred
to as the angle of incidence.
Angle
of flash coverage
The measurement in degrees of the angle formed by lines projecting
from the centre of the flash to the extremities of the field of coverage.
Angle
of View
The area of an image that a lens covers. Angle of view is determined
by the focal length of the lens. A wide-angle lens (short-focal-length)
includes more of the scene-a wider angle of view-than a normal (normal-focal-length)
or telephoto (long-focal-length) lens.
ANSI
Is a rating for photographic materials devised by the American National
Standards Institute.
Anti-fogging
agent
Constituent of a developer that inhibits or reduces fogging during
development.
Anti-halation
backing
A dye used on backs of most films capable of absorbing light which
passes through the emulsion. This way it reduces the amount extraneous
light can be reflected from the camera back through the emulsion.
Anti-reflection
coating
One or more thin layers of refractive material ( often magnesium fluoride
) coated upon the surface of a lens to minimize surface reflection.
It is deposited on the lens by vaporization of the metal in vacuum.
Aperture
The opening in a camera lens through which light passes to expose
the film. The size of aperture is either fixed or adjustable. Aperture
size is usually calibrated in f-numbers-the larger the number, the
smaller the lens opening.
Aperture priority
An exposure mode on an automatic or auto-focus camera that lets you
set the aperture while the camera sets the shutter speed for proper
exposure. If you change the aperture, or the light level changes,
the shutter speed changes automatically. Apart from the sport or action
arena, aperture priority is the most common & effective automatic
preference in photography. It can also explained as automatic exposure
system in which the lens aperture is set by the photographer, and
the camera sets the shutter speed. Can be used in the stop-down mode
with any lens that does not interfere with the metering system.
Aperture
ring
A ring, located on the outside of the lens usually behind the focusing
ring, which is linked mechanically to the diaphragm to control the
size of the aperture; it is engraved with a set of numbers called
f-numbers or f-stops.
Aplanat
Is a lens which has been corrected for spherical aberration.
Apochromatic
The inability to bring light of all colours to the same plane of focus
is known as chromatic aberration. Light refraction is a function of
wavelength, and as such each colour is normally brought to as lightly
different plane of focus. By using complex lens designs, special glass
materials and coating, designer can bring the colours within a much
narrower focus. When such a lens is designed it is said to be Apochromatic.
Archival
Image
An image meant to have lasting utility. Processed to exacting standards
and often toned with selenium or gold. Archival images are also often
stored digitally at a high resolution and quality. The file format
most often associated with archival images is TIFF, or Tagged Image
File Format, as compared to on-screen viewing file format, which are
usually JPEG's and GIF's.
Archival
Processing
Processing designed to protect a print or negative as much as possible
from premature deterioration caused by chemical reactions.
Artificial
light
Generally the term refers to light specially set up by the photographer,
such as flash or photo lamps. Photographic emulsion have different
sensitivity to daylight and artificial light, and film may be rated
for either type.
A.S.A.
An absolute term indicating a film's sensitivity to light. The letters
stands for American Standards Association . The term as been replaced
by ISO standing for International Standards Organization.
Aspect
Ratio
The ratio of width to height in photographic prints - 2:3 in 35 mm
pictures to produce photographs most commonly measuring 3.5 x 5 inches
or 4 x 6 inches; Advanced Photo System cameras deliver three aspect
ratios as selected by the user.
Aspherical
lens
A lens whose curved surface does not conform to the shape of a sphere;
lenses are usually ground or molded with spherical surfaces; because
a spherical surface lens has difficulty in correcting distortion in
ultra-wide-angle lenses or coma in large-aperture lenses brought about
by spherical aberration, an Aspherical lens is used.
Astigmatism
A lens aberration or defect that is caused by the inability of a single
lens to focus oblique rays uniformly. Astigmatism causes an object
point to appear as a linear or oval-shaped image.
Autochrome
Early commercial colour photography process in which the principals
of additive colour synthesis were applied.
Automatic
exposure setting
Automatically adjusts the exposure to match particular light settings.
Automatic
flash
An electronic flash unit with a light-sensitive cell that determines
the length of the flash for proper exposure by measuring the light
reflected back from the subject.
Auto
focus (AF)
System by which the camera lens automatically focuses the image of
a selected part of the picture subject.
Automatic
Camera
A camera with a built-in exposure meter that automatically adjusts
the lens opening, shutter speed, or both for proper exposure.
Auto-winder
Film wind-on mechanism which moves the film on one frame each time
the shutter is released.
Available
light
The light that is present in a scene, either indoors or out, that
is not added by the photographer. Also called ambient light or existing
light.
Axis
lighting
Light pointed at the subject from a position close to the camera's
lens.
B
(Bulb) Setting
A shutter-speed setting on an adjustable camera that allows for time
exposures. When set on B, the shutter will stay open as long as the
shutter release button remains depressed.
Background
The part of the scene that appears behind the principal subject of
the picture.
Backlighting
Light coming from behind the subject, toward the camera lens, so that
the subject stands out vividly against the background. Sometimes produces
a silhouette effect.
Back-Printing
Information printed on the back of a picture by the photo-finisher.
The system standard requires the printing of frame number, film cassette
number and processing date automatically on the back of each Advanced
Photo System print; may also include more detailed information, such
as customized titles and time and date of picture-taking.
Backing
The dark coating, normally on the back of a film, but sometimes between
emulsion and the base, to reduce halation. The backing dye disappears
during the processing.
Back
focus
Distance between the back surface of the lens and the image plane,
when the lens is focused at infinity.
Baffle
A type of shield that prohibits light from entering an optical system.
Backlight
control
An exposure compensation introduced when the subject of a picture
is lit from behind ( which can fool a camera's metering system, creating
a silhouette effect ).
Back-lighting
Light coming from behind the subject.
Balance
Placement of colours, light and dark masses, or large and small objects
in a picture to create harmony and equilibrium.
Balanced fill-flash
In balanced fill-flash operation, flash output is controlled to keep
it in balance with the ambient light on the scene. Nikon offers Automatic
balanced Fill-Flash where flash output is automatically compensated
to be in balance with the ambient light.
Barn
door
Are an accessory used on spotlights and flood lamps to control the
direction of light and width of the beam.
Barrel
The chassis of a lens. It usually is cylindrical and contains the
lens element and iris diaphragm.
Barrel
distortion
A lens aberration or defect that causes straight lines to bow outward
away from the centre of the image.
Base
The material on which the emulsion is coated on film, photographic
paper or videotape. Available in a choice of materials, including
paper, cellulose, triacetate, glass.
Base+
fog
The optical density of an unexposed area of processed film. This takes
into consideration the density of both the base and the emulsion.
Base
Exposure Time
The initial exposure time used for making a "straight" print.
This is determined by using a test strip.
Batch
numbers
Set of numbers printed on packages of sensitive materials to indicate
common production coating.
Bayonet
lens mount
A method of mounting a lens onto a camera body. The lens is inserted
into the camera and given a short turn to lock it into place. Except
for a few instances, a bayonet mount camera will not accept bayonet
mount lenses made by a different manufacturer. The most common method
of lens mounting.
Bellows
The folding (accordion) portion in some cameras that connects the
lens to the camera body. Also a camera accessory that, when inserted
between lens and camera body, extends the lens-to-film distance for
close focusing.
Bellows factor
The exposure compensation necessary when focusing on close subjects,
which becomes necessary when the subject is closer than ten times
the focal length of the lens. As a lens is placed closer to the subject,
focusing the lens causes it to move farther from the film, and, therefore,
less light falls on the film. Consequently the exposure must be increased.
Between-The-Lens Shutter
A shutter whose blades operate between two elements of the lens.
Bi-concave
lens
A simple lens or lens shape within a compound lens, whose surfaces
curve toward the optical centre. Such a lens causes light rays to
diverge.
Bitmap
image
An image with 1 bit of colour information per pixel, also known as
a bitmapped image. The only colours displayed in a bitmapped image
are black and white.
Bleaching
Lightening selected areas of the image using bleaches or reducers.
The most common bleach is potassium ferricyanide. Other tonal techniques
include burning, dodging, flashing, and toning.
Blow-up
An enlargement; a print that is made larger than the negative or slide.
Blur
The art of softening the detail of a image. The process can be applied
selectively to portions of an image.
Bottom
weighted
Refers to the area of the picture that the camera will meter for exposure.
When making an auto exposure the camera is programmed to look at a
number of spots in the scene, and if the camera was designed to use
bottom weighted metering, most of those spots will be in the lower
half of the picture. (See centre weighted and exposure.)
Boom
A adjustable metal arm, attached to a firm stand, on which lighting
can be mounted. Some booms are also made to support camera.
Bounce
flash
Flash illuminating a subject by reflection off a surface as opposed
to direct flash, which is flash light aimed straight at the subject.
Bounce
Lighting
Flash or tungsten light bounced off a reflector (such as the ceiling
or walls) to give the effect of natural or available light.
Box
camera
Simple camera with a fixed, single-element lens and a light-tight
box to hold the film. The shutter and aperture are usually pre-determined
and unalterable (typically 1/25 sec at ƒ11.) Early consumer cameras
developed by George Eastman were box cameras (e.g. the “Brownie”
camera) . They could not be focused, per se. The lens was set to a
hyper-focal distance that gave acceptably-sharp pictures if the subject
was a given distance from the camera and correct exposure depended
upon bright sun illuminating the scene.
Bracketing
Taking additional pictures of the subject through a range of exposures-both
lighter and darker-when unsure of the correct exposure.
Bracket
flash
Often called handle mount flash. It comprised of one arm of the L-shaped
bracket extends under the camera body and uses the camera's tripod
socket to mount the camera on the bracket. The vertical arm of the
bracket serves as a handle and mounts a flash unit in an accessory
shoe often on top of the handle portion, but there are other methods.
Flash mounted in a bracket usually requires a separate electrical
cord to make the electrical connection between camera body and flash
unit.
Brightness
One of three dimensions of colour; the other two are hue and saturation.
The term is used to describe differences in the intensity of light
reflected from or transmitted through an image independent of its
hue and saturation
Brightness
range
The difference in luminance between the darkest and lightest areas
of the subject, in both negative and print.
Brilliance
The intensity of light reflected from a surface. It is sometimes an
alternative term for luminosity.
Built-in
light meter
A reflective exposure meter that is a built-in component of a camera
so that exposures can be easily made for the cameras position.
Bulb
A shutter setting marked B at which the shutter remains open as long
as the shutter release is held down. This is used for time exposures
that are longer than your camera's preset shutter speeds.
Bulk
film
Film produced in very long, uncut strips - rolls that are too long
to fit into cameras not equipped with a bulk camera back accessory.
Many photographers buy their film in bulk, then load the bulk film
into a “bulk film loader” which permits them to cut the
bulk film into however many frames they wish, and to load the smaller
strips into film cartridges that permit film reloading. It is an economical
way to purchase film.
Burning-In
Giving additional exposure to part of the image projected on an enlarger
easel to make that area of the print darker. This is accomplished
after the basic exposure by extending the exposure time to allow additional
image-forming light to strike the areas in the print you want to darken
while holding back the image-forming light from the rest of the image.
Sometimes called printing-in.
C-41
Processing system for colour negative film.
Cable release
Its a flexible cable used for firing a camera shutter. Particularly
useful for slow shutter speed and time exposures, when touching the
camera may cause camera vibration and blurring of the image.
Camera Angles
Various positions of the camera (high, medium, or low; and left, right,
or straight on) with respect to the subject, each giving a different
viewpoint or effect.
Camera
movements
Are mechanical system most common on large format camera which provide
the facility for lens and film plane movement from a normal standard
position.
Candle
meter
Also known as lux and defined as the illumination measured on a surface
at a distance of one meter from a light source of one international
candle power.
Candid Pictures
Un-posed pictures of people, often taken without the subject's knowledge.
These usually appear more natural and relaxed than posed pictures.
Cartridge
A light tight, factory-loaded film container that can be placed in
and removed from the camera in daylight.
Catch-light
The reflection of a light in the subject's eyes in a portrait.
Cast
An image's overall shift in colour at any point in the process, from
photography to scanning and image processing. The almost white and
almost black areas of an image tend to take on a colour -- often red,
blue, or yellow -- and display an unnatural appearance.
CC
filters
Yellow, Magenta, Cyan, Red, Green and blue filters that can change
the colour balance of the resulting pictures. These filters are most
useful for duplicating slides. They come in a range of densities from
0.025 to 0.50 . They are designated by the letters CC the density
(without the decimal), and a letter indicating the hue, for example
CC10M.
Centre
weighted
Refers to the area of the picture that the camera will meter for exposure.
When making an auto exposure the camera is programmed to look at a
number of spots in the scene, and if the camera was designed to use
centre weighted metering, most of those spots will be in the centre
area of the picture.
Changing
Bag
A light proof black fabric bag that permits film and other light-sensitive
materials to be handled in normal room light. Has a double zipper
on one end and two armholes with elastic sleeves on the other.
Characteristic Curve Regions
The characteristics curves are shaped similar to a ski ramp, with
the bottom portion sloping up slightly (called the "toe"),
a steep middle portion known as the "straight line" and
a top portion that begins to flatten out (called the "shoulder").
Both film and paper characteristic curves are similar in shape.
Chromatic
aberration
An optical defect of a lens which causes different colours or wave
lengths of light to be focused at different distances from the lens.
It is seen as colour fringes or halos along edges and around every
point in the image.
Chromaticity
The colour quality of light which is defined by the wavelength ( hue
) and saturation. Chromaticity defines all the qualities of colour
except its brightness.
Chrominance
A colour term defining the hue and saturation of a colour. Does not
refer to brightness.
Cibachrome
A colour printing process that produces colour prints directly from
colour slides.
CIE
Commission Internationale de L'Éclairage. An international
group that developed a universal set of colour definition standards
in 1932.
CIE
LAB ( L*a*b* )
A colour model to approximate human vision. The model consists of
three variables: L* for luminosity, a* for one colour axis, and b*
for the other colour axis.
Clearing
Agent
A chemical that neutralizes hypo in film or paper, reducing wash time
and helping to provide a more stable image.
Clearing
time
Is the length of time needed for a negative to clear in a fixing solution.
Close-Up
A picture taken with the subject close to the camera-usually less
than two or three feet away, but it can be as close as a few inches.
Close-Up
Lens
A lens attachment placed in front of a camera lens to permit taking
pictures at a closer distance than the camera lens alone will allow.
C-mount
A threaded means of mounting a lens to a camera.
Coated
Lens
A lens covered with a very thin layer of transparent material that
reduces the amount of light reflected by the surface of the lens.
A coated lens is faster (transmits more light) than an uncoated lens.
Code
notch
Individually distinctive notches located near one corner on photographic
sheet of film for product identification purposes. When viewed correctly,
these code notches will appear at top-left corner or bottom-right
corner of the sheet. In this position the emulsion layer is always
facing away from the observer.
Cold
colours
Are colours at the blue end of the spectrum that suggest a cool atmosphere.
Cold Light Enlarger
A diffusion type of enlarger with fluorescent lamps as the light source.
These types of enlarger heads scatter the light more evenly across
the surface of the negative. One advantage of the cold light head
is that it can render more subtle tonal gradations and will minimize
the effect of dust and scratches on the negative which are translated
to the print. The cold light head does generate some heat while in
operation, but considerably less than its condenser enlarger counterpart.
Colour
Balance
How a colour film reproduces the colours of a scene. Colour films
are made to be exposed by light of a certain colour quality such as
daylight or tungsten. Colour balance also refers to the reproduction
of colours in colour prints, which can be altered during the printing
process.
Colour
cast
The effect of one colour dominating the overall look of an image.
Often caused by improper exposure, wrong film type, or unusual lighting
conditions when shooting the original image.
Colour
compensating filters
Gelatin filters that can be used to adjust the colour balance during
picture taking or in colour printing. Abbreviated CC filters.
Colour
conversion filters
Deeply coloured filters that enables colour film to be used with light
of a different colour temperature than it was intended. The 80-series
filters are blue enabling you to use daylight-balance film with tungsten
light; the 85-series are amber and let you see tungsten film with
daylight or electronic flash.
Colour
correction
The process of adjusting an image to compensate for scanner deficiencies
or for the characteristics of the output device.
Colour-correction
filter
Filters used with black-and-white film to correct for the difference
in films sensitivity to colour as compared with that of the human
eye. Without a filter, for example clouds would be all but invisible
against a light blue sky; a yellow filter would darken the sky, thus
creating contrast between the sky and the clouds.
Colour
coupler
A colourless substance contained in colour film emulsions that, when
exposed to chemical developing baths forms the colour dyes that make
up part of the layers of processed colour films.
Colour
curves
A mechanism for controlling colour changes, and matching colours.
Colour curves are set by user-adjustable lookup tables that define
a colour transform, which may be applied to each primary additive
colour in the image.
Colour
depth
The amount of colour information recorded by each CCD pixels. The
greater the depth, expressed in bits, the truer and richer the colour
is recorded.
Colour
gamut
The range of colours that can be formed by all possible combination
of colorants in any colour input system.
Colour
head
A device on a enlarger that contains adjustable built-in filters (yellow,
cyan and magenta) for colour printing.
Colour
negative
Film processed as a negative image from which positive prints can
be made.
Colour
reversal
Film designed to produce a normal colour positive on the film exposed
in the camera for subsequent viewing by transmitted light.
Colour
saturation
The purity of a colour resulting from the absence of black and white.
Colour temperature
The temperature (measured in degrees Kelvin) to which an object would
have to be heated before it would radiate a given colour. Each type
of light can also be represented by a numerical colour temperature,
here are the (rough) colour temperatures of typical lighting conditions:
Type
of light Colour temperature
Incandescent 2500K - 3500K
Twilight 4000K
Fluorescent 4000K - 4800K
Sunlight 4800K - 5400K
Cloudy daylight 5400K - 6200K
Shade 6200K - 7800K
Colour temperature meter
A device for estimating the colour temperature of a light source.
Usually used to determine the filtration needed to match the colour
balance of the light source with that of standard types of colour
film.
Colour printing filters
Yellow, Magenta and Cyan filters used when making colour prints, in
order render the colours correctly or as desired. They come in a range
of density from 0.025 to 0.50.
Coma
A lens aberration or defect that causes rays that passes obliquely
through the lens to be focused at different points on the film plane.
Compensating developer
A developer designed to compress the general contrast range in a negative
without influencing gradation in the shadow and highlight areas.
Complementary
colours
1. Any two colours of light that when combined include all the wavelengths
of light and thus produce white light.
2. Any two dye colours that when combined absorbs all wavelengths
of light and thus produce black. A colour filter absorbs light of
its complementary colour and passes light of its own colour.
Compound
shutter
Is a shutter consisting of a number of metal leaves arranged symmetrically
around the edge of the lens barrel
Composition
The pleasing, aesthetic, arrangement of the elements within a scene-the
main subject, the foreground and background, and supporting subjects.
Compur shutter
A well known German brand of compound shutter.
Condenser
An optical system which concentrates light rays from a wide source
into a narrow beam. Condensers are used in spotlights and enlargers.
Condenser Enlarger
An enlarger with a sharp, un-diffused light that produces high contrast
and high definition in a print. Scratches and blemishes in the negative
are emphasized.
Contact Print
A print made by exposing photographic paper while it is held tightly
against the negative. Images in the print will be the same size as
those in the negative.
Contrast
The range of difference in the light to dark areas of a negative,
print, or slide (also called density); the brightness range of a subject
or the scene lighting.
Contact
print
An image made by placing a negative in tight contact with a sheet
of photographic paper or other piece of film, then exposing it to
light. Although it is usually done with a photographic negative to
make a positive. Contact prints can also be made positive to negative,
or, with special types of film, positive or negative to negative.
Contact Printer
A device used for contact-printing that consists of a light tight
box with an internal light source and a printing frame to position
the negative against the photographic paper in front of the light.
Contamination
Traces of chemicals that are present where they don't belong, causing
loss of chemical activity, staining, or other problems.
Continuous
tone
An image, such as a original photographic transparency or print, in
which the tones or colours blend smoothly from one to another; also
known as a contone.
Contrast
The difference in brightness between the lightest and darkest parts
of a photographic subjects, negative, prints or slide. Contrast is
affected by the subject brightness, lighting, film type degree of
development, the grade and surface of the printing paper, and the
type of enlarger head used.
Contrast
filter
A coloured filter used on a camera to lighten or darken selected colours
in a black and white photograph. For example , a green filter used
to darken red flowers against green leaves.
Contrast Grade
Numbers (usually 1-5) and names (soft, medium, hard, extra-hard, and
ultra hard) of the contrast grades of photographic papers, to enable
you to get good prints from negatives of different contrasts. Use
a low-numbered or soft contrast paper with a high contrast negative
to get a print that most closely resembles the original scene. Use
a high-numbered or an extra-hard paper with a low-contrast negative
to get a normal contrast paper.
Contrasty.
Higher-than-normal contrast including very bright and dark areas.
The range of density in a negative or print is higher than it was
in the original scene.
Convex
lens
A simple lens which causes rays of light from a subject to converge
and form an image.
Correction
filter
A coloured filter used on a camera lens to make black and white film
produce the same relative brightness perceived by the human eye. For
example, a yellow filter used to darken a blue sky so it does not
appear excessively light.
Cool
Refers to bluish colours that by association with common objects (water,
ice, and so on) give an impression of coolness.
CP
filters
Abbreviation for colour printing filters.
Convergence
The phenomenon in which lines that are parallel in a subject, such
as the vertical lines of a building, appear nonparallel in a image.
Crossed
curves
A destructive phenomenon in image processing that causes different
colours to increase in density at different rates or gammas. The visual
effect is a colour difference from image highlight to image shadow.
Crop
(cropping)
To trim the edges of an image, often to improve the composition. Cropping
can be done by moving the camera position while viewing a scene, by
adjusting the enlarger or easel during printing or by trimming the
finished print.
Cropping
Printing only part of the image that is in the negative or slide,
usually for a more pleasing composition. May also refer to the framing
of the scene in the viewfinder.
Crossed
polarization
A system of using two polarizing filters, one over the light source
and one between the subject and the lens. Used in investigations of
stress areas in engineering and architectural models.
CMYK
The four process colours used in printing: cyan, magenta, yellow,
and black.
CMYK image
A four-channel image containing a cyan, magenta, yellow, and black
channel. A CMYK image is generally used to print a colour separation.
Dark-cloth
Material used to cover the photographer's head and camera to block
surrounding light in order to better view the image on the camera's
ground glass viewing screen.
Darkroom
A light tight area used for processing films and for printing and
processing papers; also for loading and unloading film holders and
some cameras.
Daylight film
Film balance to give correct rendition when shooting under average
daylight and flash illumination, approximately 5500K.
DCS
Desktop Colour Separation
A file format that creates four colour separations
Dedicated Flash
A fully automatic flash that works only with specific cameras. Dedicated
flash units automatically set the proper flash sync speed and lens
aperture, and electronic sensors within the camera automatically control
exposure by regulating the amount of light from the flash.
Definition
The clarity of detail in a photograph.
Dense
Describes a negative or an area of a negative in which a large amount
of silver has been deposited. A dense negative transmits relatively
little light.
Densitometer
An instrument used for measuring the optical density of an area in
a negative or print.
Density,
Image Density
Build up of silver deposits in a particular area produced by exposure
and development. The more silver present in a shadow, the more the
image density. Conversely, the less silver deposit in the highlights,
the less the image density. Technically, density is measured in terms
of the logarithm of opacity.
Depth of Field
The amount of distance between the nearest and farthest objects that
appear in acceptably sharp focus in a photograph. Depth of field depends
on the lens opening, the focal length of the lens, and the distance
from the lens to the subject. The zone of acceptable sharpness in
a picture extending in front of and behind the plane of the subject,
that is most precisely focused by the lens. It can be controlled by
varying three factors; the size of the aperture; the distance of the
camera from the subject; and the focal length of the lens. If the
photographer decrease the size of the aperture, the depth of field
increases; If the photographer focuses on a distant subject, depth
of field will be greater than if the photographer focused on a near
subject; and if he/she fitted a wide-angle lens to the camera, it
would give the photographer greater depth of field than a normal lens
viewing the same scene.
Depth
of field scale
Scale on a lens barrel showing the near and far limits of depth of
field possible when the lens is set at any particular focus and aperture.
Depth of Focus
The distance range over which the film could be shifted at the film
plane inside the camera and still have the subject appear in sharp
focus; often misused to mean depth of field.
Developer
Chemical solution used to convert the invisible silver halide crystals
in the film emulsion into visible metallic silver.
Development
1. The entire process by which exposed film or paper is treated with
various chemicals to make an image that is visible and permanent.
2. Specifically, the step in which film or paper is immersed in developer.
Developing
Tank
A light tight container used for processing film.
Diaphragm
Lens opening. A perforated plate or adjustable opening mounted behind
or between the elements of a lens used to control the amount of light
that reaches the film. Openings are usually calibrated in f-numbers.
Dichroic head
An enlarger head that contains yellow, magenta, and cyan filters that
can be moved in calibrated stages into or out of the light beam to
change the colour balance of the enlarging light.
Diffraction
When light is obstructed by an object and the wave front is changed,
interference occurs between components of the altered wave front.
The pattern formed by interference is called the diffraction pattern.
Many components are designed to yield very specific diffraction effects
(diffractive optics, gratings). Other components attempt to counteract
this process to determine more information about the obstructing medium
(electronic imaging).
Diffraction
filter
A colourless filter inscribed with a network of parallel grooves.
These break white light up into its component colours, giving a prism-like
effect to highlights.
Diffused
light
Light that has lost some intensity by being reflected or by passing
through a translucent material. Diffusion softens light, eliminating
both glare and harsh shadows, and thus can be of great value in photography,
notably in portraiture.
Diffuser
A material that softens light passing through it. The effect is to
soften the character of light. The closer a diffuser is to a light
source the less it scatters light.
Diffusing
Softening detail in a print with a diffusion disk or other material
that scatters light.
Diffusion-Condenser Enlarger
An enlarger that combines diffuse light with a condenser system, producing
more contrast and sharper detail than a diffusion enlarger but less
contrast and blemish emphasis than a condenser enlarger.
Diffusion Enlarger
An enlarger that scatters light before it strikes the negative, distributing
light evenly on the negative. Detail is not as sharp as with a condenser
enlarger; negative blemishes are minimized.
Dilution
The reduction in the strength of a liquid by mixing it with an appropriate
quantity of water.
Dioptre
Optical term for the power of a lens. Photographically, it is typically
used to indicate the magnification and focal length of close-up lenses.
Dioptre
correction
This is like a focus adjustment that matches the focus of the camera's
optical viewfinder to the user's eyesight. This way, users don't have
to wear their glasses when using the camera. As some of the viewfinders
are quite small and difficult to use with your glasses on dioptre
correction can be a welcome option for eyeglass wearers.
Direct
positive
A high contrast positive image slide made only from camera ready originals
with no negative required.
Dispersion
Light rays of different wavelengths deviate different amounts through
a lens causing a rainbow effect around points and edges.
Distortion
A phenomenon in which straight lines are not rendered perfectly straight
in a picture. There are two types of distortion--barrel distortion
and pincushion distortion. Distortion cannot be improved by stopping
down the lens.
Diverging
lens
A lens which causes rays of light coming from the subject to bend
away from the optical axis.
D/log
E curve
A graph of density (D) against the logarithm of exposure (log E) Used
in sensitometry to compare the sensitivity of different emulsions
to light.
D-max
Maximum density. The greatest density in an image. Also, the greatest
density possible for a particular film or paper.
D-min
Minimum density. The smallest density in a image. Also, the smallest
density possible for a particular film or paper.
DPI
Dots per inch: a measure of image resolution.
Dodging
Holding back the image-forming light from a part of the image projected
on an enlarger easel during part of the basic exposure time to make
that area of the print lighter. Other tonal techniques include burning,
flashing, toning, and bleaching.
Double
Exposure
Two pictures taken on one frame of film, or two images printed on
one piece of photographic paper.
Drying
cabinet
Is a vented cabinet equipped with suspension clips for drying films.
Drying
marks
Are marks on the film emulsion caused by uneven drying and resulting
in areas of uneven density, which may show up in the final print.
Dry
mounting tissue
A thin paper coated with adhesive on both sides for permanently adhering
a photograph to a support. The adhesive is softened by heat and hardens
when it cools.
Dupes
A copy of a slide or transparency made without an inter-negative or
special duplicating film. Frequently used as an intermediate image
for other print subjects.
DX Data Exchange
Electrical coding system employed in 35 mm format film that communicates
film speed, type and exposure length to the camera.
E-6
Chemical processing system for most colour-reversal (slide) film.
Easel
A device to hold photographic paper flat during exposure, usually
equipped with an adjustable metal mask for framing.
Edge
numbers
The reference numbers printed by light at regular intervals along
the edge of 35mm and roll films during manufacture.
EI
see exposure index
Emulsion
Micro-thin layers of gelatine on film in which light-sensitive ingredients
are suspended; triggered by light to create a chemical reaction resulting
in a photographic image.
Emulsion
Side
The side of the film coated with emulsion. In contact printing and
enlarging, the emulsion side of the film-dull side-should face the
emulsion side of the photo paper-shiny side.
Enlargement
A print that is larger than the negative or slide; blow-up.
Enlarger
A device consisting of a light source, a negative holder, and a lens,
and means of adjusting these to project an enlarged image from a negative
onto a sheet of photographic paper.
Existing Light
Available light. Strictly speaking, existing light covers all natural
lighting from moonlight to sunshine. For photographic purposes, existing
light is the light that is already on the scene or project and includes
room lamps, fluorescent lamps, spotlights, neon signs, candles, daylight
through windows, outdoor scenes at twilight or in moonlight, and scenes
artificially illuminated after dark.
Exposure
The quantity of light allowed to act on a photographic material; a
product of the intensity (controlled by the lens opening) and the
duration (controlled by the shutter speed or enlarging time) of light
striking the film or paper.
Exposure
compensation
Many camera have the ability to force the camera to overexpose or
underexpose an image during capture. This can be done for effect or
to compensate for some particular lighting situation. This is often
referred to as EV compensation.
Exposure
factor
A figure by which the exposure indicated for an average subject and/or
processing should be multiplied to allow for non-average conditions.
Usually applied to filters. Occasionally to lighting. Processing,
etc Not normally used with through-the-lens exposure meters.
Exposure
index ( EI )
A film speed rating similar to an ISO rating abbreviated EI.
Exposure
Latitude
The range of camera exposures from underexposure to overexposure that
will produce acceptable pictures from a specific film.
Exposure Meter
An instrument with a light-sensitive cell that measures the light
reflected from or falling on a subject, used as an aid for selecting
the exposure setting. The same as a light meter.
Expiry
date
The date stamp on most film boxes indicating the useful life of the
material in terms of maintaining its published speed and contrast.
Extension
tubes
Tubes made from metal and, more frequently, plastic inserted between
the lens and the camera, thereby making the lens to film distance
greater. The result is increased magnification for close-up photography.
Extension
bellows
Device used to provide the additional separation between lens and
film required for close-up photography.
EV
see exposure value
Eye
light
A highlight in the eye or the small light placed near the camera to
produce it.
Eyepiece
shutter
A built-in device that prevents light from entering the viewfinder
eyepiece.
Factor
See filter factor
Fading
The loss of or change of colour density, generally accelerated by
exposure to sunlight.
Falloff
Decrease in the intensity of light as it spreads out from the source.
Fast
film
Is film which has an emulsion that is very sensitive to light. These
film have high ISO ratings.
Fast
lens
Is a lens with a wide maximum aperture ( low f number ).
Fibre Based Paper
Photographic paper without a resin (plastic) coating. Processing times
are longer than for other papers, but the paper probably has more
archival permanence than resin coated papers.
(See other paper types: variable contrast, graded contrast, resin
coated.)
Field
curvature
A lens aberration or defect that causes the image to be formed along
a curve instead of on a flat plane.
Fill-In
Light
Additional light from a lamp, flash, or reflector; used to soften
or fill in the shadows or dark picture areas caused by the brighter
main light. Called fill-in flash when electronic flash is used.
Fill-flash
A technique that uses flash illumination as a supplement to ambient
light. Useful when photographing subjects that are backlit, with very
high-contrast lighting or in shadow.
Film
A photographic emulsion coated on a flexible, transparent base that
records images or scenes.
Film
base
Flexible support on which light sensitive emulsion is coated.
Film
Characteristic Curve
This curve describes a graphical relationship between the logarithm
of the exposure value (horizontal axis) and density (vertical axis)
of film. Each brand of film may exhibit a different characteristic
curve.
Film
clips
Metal or plastic clips used to prevent the curling of the film during
the drying.
Film
holder
A light-tight, removable device for holding film on many medium-format.
This allows the photographer to preload the film so he can quickly
change rolls of film.
Film
leader
Length of protective film at the beginning of a roll of unexposed
or processed film.
Film
plane
The plane on which the film lies in a camera. The camera lens is designed
to bring images into focus precisely at the film plane in a camera
to ensure correctly exposed pictures.
Film
pressure plate
A part of the camera back which, when closed against the film guide
rails, creates a very precise tunnel in which the film is flatly positioned
for sharpness.
Film
Speed
The sensitivity of a given film to light, indicated by a number such
as ISO 200. The higher the number, the more sensitive or faster the
film. Note: ISO stands for International Standards Organization.
Filter
A coloured piece of glass or other transparent material used over
the lens to emphasize, eliminate, or change the colour or density
of the entire scene or certain areas within a scene.
Filter
factor
The increased exposure needed to compensate for the amount of light
absorbed by a filter. A factor of two indicates you need to give the
film one stop more exposure; a factor of three needs two stops and
a factor of six needs three stops more.
Filter
pack
Several filters used together, as in a enlarger for colour printing
or when duplicating slides, in order to obtain the best or desired
colour in the image.
Fine
grain
Film or developer that produces images in which areas of uniform tone
appear smooth, with no clumping of the silver particles that form
the image.
Fine
grain developers
Are film developers which help to keep grain size in the photographic
image to a minimum.
Finder
A viewing device on a camera to show the subject area that will be
recorded on the film. Also known as viewfinder and projected frame.
Fisheye
lens
Extreme wide-angle lens with an angle of view exceeding 100 degree
and sometimes in excess of 180 degree. depth of field is practically
infinite and focusing is not required.
Fixed-Focus
Describes a non-adjustable camera lens, set for a fixed subject distance.
Fixed-Focus Lens
A lens that has been focused in a fixed position by the manufacturer.
The user does not have to adjust the focus of this lens.
Fixer
A chemical solution (sodium thiosulfate or ammonium thiosulfate) that
makes a photographic image sensitive to light. The fixer stabilizes
the emulsion by converting the undeveloped silver halides into water-soluble
compounds, which can then be dissolved away. Also called hypo.
Fixing Bath
A solution that removes any light-sensitive silver-halide crystals
not acted upon by light or developer, leaving a black-and-white negative
or print unalterable by further action of light. Also referred to
as hypo.
Flare
The soft effect visible in a picture resulting from stray light which
passes through the lens but is not focused to form the primary image.
Flare can be controlled by using optical coating, light baffles and
low reflection surfaces , or a lens hood.
Flash
A brief, intense burst of light from a flashbulb or an electronic
flash unit, usually used where the lighting on the scene is inadequate
for picture-taking.
Flash
factor
Is a number which provides a guide to correct exposure when using
Flash. See also Guide number
Flash
meter
A device for measuring the light coming from a electronic flash and
indicating the appropriate aperture for correct exposure. Some flash
meter can also measure the ambient light.
Flash
range
The maximum distance from which a flash can effectively illuminate
a subject. Most built-in flashes are effective to about 12-15 feet.
Range varies by brand, so check the specification carefully.
Flash
sync
A special socket on a camera that allows the attachment of an auxiliary
strobe light for flash pictures. It is synchronized to the camera's
shutter so the light goes off at the right time.
Flashing
Pre-exposing the paper to a very diffused white light in order to
reduce the contrast level between the highlights and shadows and extend
the tonal range. Other tonal techniques include burning, dodging,
toning, and bleaching.
Flat
Too low in contrast. The range in density in a negative or print is
too short.
Flat
Lighting
Lighting that produces very little contrast or modeling on the subject
plus a minimum of shadows.
Floodlight
An electric light designed to produce a broad, relatively diffused
beam of light.
f-Number or f-Stop.
A number that indicates the size of the lens opening on an adjustable
camera. The common f-numbers are f/1.4, f/2, f/2.8, f/4, f/5.6, f/8,
f/11, f/16, and f/22. The larger the f-number, the smaller the lens
opening. In this series, f/1.4 is the largest lens opening and f/22
is the smallest. Also called f-stops, they work in conjunction with
shutter speeds to indicate exposure settings.
Focal
Length
The distance between the film and the optical centre of the lens when
the lens is focused on infinity. The focal length of the lens on most
adjustable cameras is marked in millimetres on the lens mount.
Focal
plane
The plane on which the image of a subject is brought to focus behind
the lens. To produce a sharp picture, the lens must be focused so
that this place coincides with the plane on which the film sits. Also
called the film plane.
Focal-Plane Shutter
An opaque curtain containing a slit that moves directly across in
front of the film in a camera and allows image-forming light to strike
the film.
Focal
point
The point on a focused image where the rays of light intersect after
reflecting from a single point on a subject.
Focus
Adjustment of the distance setting on a lens to define the subject
sharply.
Focusing
System of moving the lens in relation to the image plane so as to
obtain the required degree of sharpness of the film.
Focusing
cloth
A dark cloth used in focusing a view camera. The cloth fits over the
camera back and the photographer's head to keep out light and to make
the ground glass image easier to see.
Focus Range
The range within which a camera is able to focus on the selected picture
subject - 4 feet to infinity - for example.
Focusing
screen
Used for focusing on a subject or composing a picture; the focusing
screen is located at a position equivalent to that of the film plane.
To provide dispersion, a matte field made of specially ground glass
or plastic is generally used for focusing screens.
Fog
An overall density in the photographic image cause by unintentional
exposure to light or unwanted chemical activity.
Fogging
Darkening or discolouring of a negative or print or lightening or
discolouring of a slide caused by
exposure to non-image-forming light to which the photographic material
is sensitive, too much handling in air during development, over-development,
outdated film or paper, or storage of film or paper in a hot, humid
place.
Forced
Development
(See Push-processing)
Foreground
The area between the camera and the principal subject.
Four-colour process printing
The basic method of recreating a broad spectrum of colours on a printing
press.
Frame
One individual picture on a roll of film. Also, tree branch, arch,
etc., that frames a subject.
Fresnel
Pattern of a special form of condenser lens consisting of a series
of concentric stepped rings, each ring a section of a convex surface
which would, if continued, form a much thicker lens. Used on focusing
screens to distribute image brightness evenly over the screen.
Front lighting
Light shining on the side of the subject facing the camera.
G
curve
Is an average gradient of a characteristic curve, describing similar
characteristics to gamma, but measuring the slope from a line joining
the lower and upper of the curve actually used in practice.
Gelatine
The medium used on photographic materials as a means of suspending
light-sensitive silver halides.
Gelatine
filter
Are filters cut from dyed gelatine sheets and held in front of the
lens or studio light.
Ghost
image
In time exposure photography, an object that is only partially recorded
on the film and therefore has a translucent, ghost-like appearance.
Some people also refer to " flare " as a ghost image.
Glossy
Describes a printing paper with a great deal of surface sheen. Opposite:
matte.
Gradation
A smooth transition between black and white, one colour and another,
or colour and no-colour.
Graded
Contrast
Printing paper containing a single layer of emulsion of a specific
contrast range. To change the overall contrast level, you must change
to another grade of paper. (See other paper types: variable contrast,
resin coated, fibre based.)
Grades,
Paper Grades
A classification system for specifying the degree of paper contrast,
ranging from 0 (very soft) to 5 (very hard).
(See paper types: variable contrast, graded contrast, resin coated,
fibre based.)
Gradient
A smooth spread between colours.
Grain
Clumps of silver-halide grains in film and paper that constitute the
image. These grains are produced both in the exposure process (film
grain) and in the development process (paper grain). Unlike film,
the grain in printing paper is largely responsible for the image tone.
Graininess is most noticeable in even, mid-tone areas of a print.
Graininess
The sand-like or granular appearance of a negative, print, or slide.
Graininess becomes more pronounced with faster film and the degree
of enlargement.
Grey
card
A card that reflects a known percentage of the light falling on it.
Often has a grey side reflecting 18 percent and a white side reflecting
90 percent of the light. Used to make accurate exposure meter readings
(meter base their exposures on a grey tone of 18 percent reflectance)
or to provide a known grey tone in colour work.
Grey
level
A shade of grey assigned to a pixel. The shades are usually positive
integer values taken from the grey-scale. In a 8-bit image a grey
level can have a value from 0 to 255.
Grey
scale
An image type that contains more than just black and white, and includes
actual shades of grey. In a greyscale image, each pixel has more bits
of information encoded in it, allowing more shades to be recorded
and shown. 4 bits are needed to reproduce up to 16 levels of grey,
and 8 bits can reproduce a photo-realistic 256 shades of grey.
Greyscale
image
An image consisting of up to 256 levels of grey, with 8 bits of colour
data per pixel.
Ground
glass
A piece of glass roughened on one side so that an image, focused on
it can be seen on the other side.
Guide
number
A number used to calculate the f-setting (aperture) that correctly
exposes a film of a given sensitivity (film speed) when the film is
used with a specific flash unit at various distances from flash to
subject. To find out the f-setting, divide the guide number by the
distance.
Halation
Is a diffused ring of light typically formed around small brilliant
highlight areas in the subject. It is caused by light passing straight
through the emulsion and being reflected back by the film base on
the light sensitive layer. This records slightly out of register with
the original image.
Halftone
The reproduction of a continuous-tone image, made by using a screen
that breaks the image into various size dots.
Halo
A light line around object edges in a image, produced by the USM (sharpening)
technique.
Hanger
A frame for holding sheet film during processing in a tank.
Hard
Developer
A paper developer that can be used alone or in combination with other
developers (two-bath development). When used alone, a hard developer
can produce a wide range of tones. Contrast can be varied by changing
paper grades, changing filtration, or using a softer developer to
obtain intermediate contrast grades.
(See paper types: variable contrast, graded contrast, resin coated,
fibre based.)
Hardeners
Are chemicals often used with a fixing bath to strengthen the physical
characteristics of an emulsion. The most common hardeners are potassium
or chrome alum.
H&D
curve
Another name for the D/log E curve, after its originators, Ferdinand
Hurter and Vero C. Driffield.
High
Contrast
A wide range of density in a print or negative.
High
key
A light image that is intentionally lacking in shadow detail.
Highlights
The whitest or brightest part of an image; the opposite of shadows.
Highlight
Separation, Highlights
Important bright areas (highlights) of a scene in which detail must
be recorded (exposed) onto the film. Highlights are represented on
a negative by dense deposits of black metallic silver, reproducing
as the bright areas on a print. (Also see shadow detail.)
Honeycomb
Grid which makes light from a flash (or other source) more directional,
like a spot rather than a flood.
Hot
Shoe
The fitting on a camera that holds a small portable flash. It has
an electrical contact that aligns with the contact on the flash unit's
"foot" and fires the flash when you press the shutter release.
This direct flash-to-camera contact eliminates the need for a PC cord.
Hot-spot
Concentration of light in a particular area.
Hue
The aspect of colour that distinguished it from another colour (what
makes a colour red, green, or blue). Hue is distinct from saturation,
which measures the intensity of the hue.
Hyperfocal
Distance
Distance of the nearest object in a scene that is acceptably sharp
when the lens is focused on infinity.
Hypo
The name for a fixing bath made from sodium thiosulfate, other chemicals,
and water; often used as a synonym for fixing bath.
Hypo
Clear
Chemical solutions used to speed up the efficient removal of fixer
from the prints in subsequent water washings of the prints.
Image
plane
Is the plane commonly at right angles to the optical axis at which
a sharp image of the subject is formed. The nearer the subject is
to the camera, the greater the lens image plane distance.
Image resolution
The amount of data stored in an image file, measured in pixels per
inch (ppi).
Incandescent
lamp
An electrical lamp in which the filament radiates visible light when
heated in a vacuum by an electrical current.
Incident
Light
Light falling onto a surface, not reflected from it (reflected light).
Incident
meter
A hand-held Exposure meter that measures the intensity of light falling
on the subject. To use it, you usually aim the hemispheric dome toward
the camera. Most incident meter can also be used in a mode to measure
reflected light.
Indoor
film
Film formulated to give correct colour rendition when photographing
subjects under 3200K light. It is also called "tungsten"
film. Most film is balance for daylight and if you use daylight film
with household lamps or photographic lamps, the colours will be slightly
reddish or orange. The light from an electronic flash is similar in
colour rendition to daylight.
Infinity
In photographic terms is a distance great enough to be unaffected
by finite vibration. In practice this relates to most subjects beyond
1000 meters or in landscape terms, the horizon. When the infinity
distance is within the depth of field all objects at that distance
or farther will be sharp.
Infrared
The region of the electromagnetic spectrum adjacent to the visible
spectrum, just beyond red with longer wavelengths.
Integration
Integration in photographic analysis is defined as the method of averaging
all density ( illumination ) values either in R, G, and B, or as neutral
density and saving this aggregate value to determine exposure in the
camera or the darkroom.
Intensity
The relative brightness of a portion of the image or illumination
source.
Inter-negative
A negative created directly from a colour-reversal (positive) or black-white
positive film. It is the negative copy of the camera original.
Inter-positive
A positive transparency image generated as an intermediate step to
enlarge an image in positive form either from a negative or positive
material.
Inverse
square law
A law of physics that states that light from a point source fall off
inversely to the square of the distance. As a example, if a light
is 10 feet from your subject and you move it to 20 feet, you'll only
have 1/4 the lighting intensity. If you move the light to 40 feet,
it will now have only 1/16th the intensity.
Inverting
Creating a negative of an image
ISO
Speed
The emulsion speed (sensitivity) of the film as determined by the
standards of the International Standards Organization. In these standards,
both arithmetic (ASA) and logarithmic (DIN) speed values are expressed
in a single ISO term. For example, a film with a speed of ISO 100/21°
would have a speed of ASA 100 or 21 DIN.
JPEG
Joint Photographic Experts Group. This group established a standard
method for compressing and decompressing digitised photos or images.
The high-resolution images provided with Photo Disc are compressed
according to JPEG standards.
K
14
Kodak's chemical process for developing Kodachrome slides.
K
(Kelvin)
Abbreviation for Kelvin temperature, the measurement of the redness
or blueness of white light. This is written without the degree sign.
Daylight at noon, for example, has a Kelvin temperature of about 5500K,
while photographic tungsten lamps are 3200K. Technically it is a measurement
of the colour of white or grey based on the temperature to which a
black body must be heated to produce that colour of white.
Key
light
A studio light used to control the tonal level of the main area of
the subject.
Key-stoning
Distortion of a projected image when the projector is not directed
perpendicular to the screen.
Lamp
A general term used to describe the various kinds of artificial light
sources used in photography.
Lantern
slides
Is a old term used to described transparencies.
Large
format camera
Is a general term for any camera having a picture format of 4x5 inches
or larger.
Latent
Image
The invisible image left by the action of light on photographic film
or paper. The light changes the photosensitive salts to varying degrees
depending on the amount of light striking them. When processed, this
latent image will become a visible image either in reversed tones
(as in a negative) or in positive tones (as in a colour slide).
Lateral
reversal
A mirror image, as seen in the viewfinders of some cameras where the
scene appears flipped from left to right.
Latitude
Is the degree by which exposure can be varied and still produce an
acceptable image. The degree of latitude varies by film type. Faster
films tend to have greater latitude than slower films.
LCD panel
Liquid Crystal Display on cameras that shows such information as remaining
exposures, flash status and aspect ratio selected.
Leaf shutter
A camera mechanism that admits light to expose film by opening and
shutting a circle of overlapping metal leaves.
Lens
One or more pieces of optical glass or similar material designed to
collect and focus rays of light to form a sharp image on the film,
paper, or projection screen. A lens made of a single piece of glass
cannot produce very sharp or exact images, so camera lenses are made
up of a number of glass "elements" that cancel out each
other's weakness and work together to give a sharp true image. The
size, curvature and positioning of the elements determine the focal
length and angle of view of a lens.
Lens
aperture (f/)
The physical opening of a lens. The smaller the f/number the more
light passes through.
Lens
barrel
A metal or plastic tube with a blackened inner surface, in which the
lens elements and mechanical components of the lens are mounted.
Lens
cap
Is a plastic, rubber or metal cover which fits over the front or back
of the lens to protect it.
Lens
coating
A layer or multiple layers of thin anti-reflective materials applied
to the surface of the lens elements to reduce light reflection and
increase the amount of transmitted light.
Lens Shade
A collar or hood at the front of a lens that keeps unwanted light
from striking the lens and causing image flare. May be attached or
detachable, and should be sized to the particular lens to avoid a
vignette.
Lens-Shutter
Camera
A camera with the shutter built into the lens; the viewfinder and
picture-taking lens are separate.
Lens
Speed
The largest lens opening (smallest f-number) at which a lens can be
set. A fast lens transmits more light and has a larger opening than
a slow lens.
Light-box
A box of fluorescent tubes balanced for white light and covered with
translucent glass or plastic. Used for viewing, registering or correcting
prints , film negatives and positives.
Light
meter
Is an alternate term for exposure meter.
Light
sources
A general term applied to any source of light used in photography.
Lighting
ratio
The ratio between the key and fill lights.
Light-tight
Refers to any room or containers that is absolutely dark inside, allowing
no unwanted light to penetrate.
Line
art copy
Images containing only black and white pixels. Line art may also include
one-colour image, such as mechanical blue prints or drawings.
LPI
Lines per inch.
A measure of resolution, usually screen frequency in halftones.
Lithium
Some of the newer digital cameras are now coming with a lithium rechargeable
battery pack. Lithium batteries are lighter and more costly than NiMH
or NiCad type of rechargeable cells and can be rapidly charted.
Lith
film
A type of film made primarily for use in graphic arts and printing.
It produces an image with very high contrast.
Low
key
A dark image that is intentionally lacking in highlight detail.
Luminance
Lightness. The highest of the individual RGB values plus the lowest
of the individual RGB values, divided by two; a component of Hue-Saturation-
Lightness image.
Luminosity
The brightness of either a light source or a reflective surface.
Lux
A measurement of the light intensity. One Lux in video means light
level of a candle light. l Lux approximately equals to 10 foot-candles
(1 Lux = 10.764 fc).
Macro
attachment
These are supplementary elements attached to the front of a normal
lens to give an extreme close-up facility.
Macro
Lens
A lens that provides continuous focusing from infinity to extreme
close-ups, often to a reproduction ratio of 1:2 (half life-size) or
1:1 (life-size).
Magazine
A light tight metal container (cartridge) that holds 135 film (cylindrical
magazine).
Main
light
Same as " Key light " the principal source of light, usually
in a studio, and generally the brightest light on a subject or scene.
Manual
exposure
A mode of camera operation in which all exposure settings are determined
and set by the photographer.
Mid
tones
An area of medium brightness, neither a very dark shadow not a very
bright highlight. A medium grey tone in a print.
Mini-lab
Photo-finishing operation that operates on a retail level, serving
consumers directly and processing film on-site.
Modeling
light
A light built into a flash unit that remains on while the flash is
turned or on standby mode, permitting the photographer to assess highlight
and shadow areas that will be created when subsequently exposing the
film in the brighter light of the flash.
Moiré
pattern
An undesirable pattern in colour printing, resulting from incorrect
screen angles of overprinting halftones. Moiré patterns can
be minimized with the use of proper screen angles.
Mono
bath
Is a single solution which combines developer and fixer for processing
b&w negatives. It is a quick simple system but does not allow
for development control.
Monochrome
Single-coloured. An image or medium displaying only black and white
or greyscale information. Greyscale information displayed in one colour
is also monochrome.
Monopod
A one-leg stand for holding the camera steady.
Monorail
Large format camera (usually, though there are medium format examples)
constructed on an " optical bench " principle with front
and rear standards on a rail.
Motor
Drive
A mechanism for advancing the film to the next frame and re-cocking
the shutter, activated by an electric motor usually powered by batteries.
Popular for action-sequence photography and for recording images by
remote control.
Mounting
press
Also called a dry-mounting press. A device that provides both pressure
and heat, for mounting a photograph on a support, using a tissue coated
with heat-softenable adhesive.
Mounting
tissue
Also called mounting tissue. A thin paper coated with adhesive on
both sides for permanently adhering a photograph to a support. The
adhesive is softened by heat and hardens when it cools.
Movements
Large format camera movements to help focus, shape, composition or
converging angles (swing, shift & tilt ).
Multiple
exposure
More than one exposure on the same frame of film. Called a "
Double-exposure " when there are two exposures on a single film
frame.
ND
Filter or Neutral Density Filter
A filter that attenuates light evenly over the visible light spectrum.
It reduces the light entering a lens, thus forcing the iris to open
to its maximum.
Negative
The developed film that contains a reversed tone image of the original
scene.
Negative
Holder
A device designed to hold the negative in proper position in an enlarger.
Neutral
density filter
Describes a grey camera filter which has a equal opacity to all colours
of the spectrum and so does not affect the colours in the final image.
It is used to reduce the amount of light entering the camera when
apertures or shutter must remain constant.
Newton
rings
A pattern of concentric, multi-coloured, rainbow like rings occasionally
introduced into a scanned or enlarged image and caused by contact
of the transparency, or negative film, with the glass plate used in
some scanners or enlargers. Using Anti Newton glass within the negative
carrier/scanner can reduce or eliminate the rings.
Nickel
cadmium (NiCad)
Rechargeable batteries that use an alkaline electrolyte. They have
a longer life than non-rechargeable batteries. NiCad batteries have
a memory, so they need to be run all the way down before recharging.
Otherwise, they will begin to run out of power sooner.
Nickel
metal hydride (NiMH)
A rechargeable battery that lasts longer than a NiCad and has no memory,
so it is easier to manage.
Normal
Lens
A lens that makes the image in a photograph appear in perspective
similar to that of the original scene. A normal lens has a shorter
focal length and a wider field of view than a telephoto lens, and
a longer focal length and narrower field of view than a wide-angle
lens. With 35mm cameras the standard lens is usually 50mm.
Notching
code
Notches cut in the margin of sheet film so that the type of film and
its emulsion side can be identified in the dark.
Off-The-Film
Metering
A meter which determines exposure by reading light reflected from
the film during picture-taking.
Ortho
(Orthochromatic)
Denotes film sensitive to blue and green light.
Opacity
The degree to which an object blocks light. Technically, opacity is
expressed as a ratio of the incident light to the transmitted light.
Opening
up
Is increasing the size of the lens aperture or decreasing the shutter
speed to admit more light to the film.
Optical
axis
Is an imaginary line passing horizontally through the centre of a
compound lens system.
Optical
viewfinder
A viewfinder system that shows a similar view to that seen by the
camera lens ( as on 35mm compact cameras ) Useful because it uses
no power, but can cause parallax and focus errors.
Optical
Zoom
An optical zoom is made to bring you closer to your subject, without
you having to move. Zooms are constructed to allow a continuously
variable focal length, without disturbing focus. To achieve this,
the optical zoom uses a combination of lenses that magnify the image
prior to being registered at high resolution by the sensor. While
the digital zoom only changes the presentation of existing data, the
optical zoom actually augments the data collected by the sensor. Optical
zooms are superior to digital zooms.
Orthochromatic
( Ortho film )
Black-and-white emulsions that are not equally sensitive to all colours
of light. They are more sensitive to blue and green, but not sensitive
to red light.
Out-of-focus
Refers to an image created when the rays of light passing through
a lens fall upon a plane in front of or beyond the point at which
they converge to form a sharp image. Out-of-focus images appear blurred
or fuzzy.
Overdevelop
To give more than normal the amount of development.
Overexposure
A condition in which too much light reaches the film, producing a
dense negative or a very light slide.
Oxidation
Loss of chemical activity due to contact with oxygen in the air.
Paper
base
Is the support for the emulsion used in printing papers.
Paper
Characteristic Curve
This curve describes a graphical relationship between exposure values
(horizontal axis) and image density (vertical axis) of a printing
paper. Each brand of paper may have a different initial characteristic
curve and graded paper curves will be different than variable contrast
paper curves. The shape of the curve can be altered by different developers,
development times, temperatures, and toning.
Paper
safe
Is a light-tight container for unexposed photographic papers, with
an easy open positive closing lid.
Paper
grade
Is a numerical terminological description of paper contrast: numbers
0-1 soft; numbers 2 normal; number 3 hard; number 4-5 very hard; number
6 ultra hard. Similar grade number from different manufactures do
not have the same characteristics.
Pan
(Panchromatic)
Designation of films that record all colours in tones of about the
same relative brightness as the human eye sees in the original scene,
sensitive to all visible wave-lengths.
Panning
Moving the camera so that the image of a moving object remains in
the same relative position in the viewfinder as you take a picture.
Panorama
A broad view, usually scenic.
Panoramic
camera
Camera with a special type of scanning lens which rotates. Or a static
lens camera with a wide format e.g. 6cm x 17cm.
Parallax
With a lens-shutter camera, parallax is the difference between what
the viewfinder sees and what the camera records, especially at close
distances. This is caused by the separation between the viewfinder
and the picture-taking lens. There is no parallax with single-lens-reflex
cameras because when you look through the viewfinder, you are viewing
the subject through the picture-taking lens.
Parallax
error
Occurs when shooting very close up with a viewfinder camera. The photographer
does not see an accurate indication of the subjects position relative
to the lens, so parts of the subject that he or she thinks will be
photographed are missing on the final photograph. Parallax error is
overcome in more expensive compact and viewfinder cameras which adjust
the viewfinder to compensate for the distance the subject is away
from the camera.
Parallax
focus
Focusing system in some compact cameras that compensates for the difference
between viewfinder and lens placement.
Perforations
Regularly and accurately spaced holes punched throughout the length
of 35 mm film for still cameras.
Photo
File Index Print
A basic system feature that makes ordering reprints and enlargements
easy; the small print shows a positive, "thumbnail"-sized
version of every picture on an Advanced Photo System film roll; accompanies
all prints and negatives returned in the sealed film cassette by the
photo-finisher; each thumbnail picture is numbered on the index print
to match negative frames inside the cassette.
Photomontage
A photographic composition assembled from pieces of different photographs
or of different negatives, closely arranged or superimposed upon each
other. Sometimes graphic material is added to the combination.
PICT
A standard file format for exchanging graphics or image information.
Pincushion
distortion
A lens aberration or defect that causes straight lines to bow inward
toward the centre of the image.
Pinhole
1. A small clear spot on a negative usually caused by dust on the
film during exposure or development or by a small air bubble that
keeps developer from the film during development.
2. The tiny opening in a pinhole camera that produces an image.
Pinhole
Camera.
A simple camera that utilises the properties of the pinhole lens.
PPI
Pixels per inch, a measure of the resolution of a computer display
or digital image.
Pixel
A single dot on a computer display or in a digital image.
Plane
of focus
The point in a camera where all the light rays converge, forming a
sharp image. In a camera, this corresponds to the film plane.
Polarizing
Screen (Filter)
A filter that transmits light traveling in one plane while absorbing
light traveling in other planes. When placed on a camera lens or on
light sources, it can eliminate undesirable reflections from a subject
such as water, glass, or other objects with shiny surfaces. This filter
also darkens blue sky.
Point
and shoot
A term used for a simple, easy to use camera with a minimum of user
controls. Generally the user turns the camera on , aims it at the
subject and presses the shutter button. The camera does everything
automatically.
Polarizing
filter
A filter that reduces reflections from non-metallic surfaces such
as glass or water by blocking light waves that are vibrating at selected
angles to the filter. Also used to darken a blue sky, thusly making
clouds stand out more.
Polaroid
back
A camera back that uses instant film for proofing a scene (checking
lighting, composition & basic exposure ) before shooting with
traditional film.
Positive
The opposite of a negative, an image with the same tonal relationships
as those in the original scenes-for example, a finished print or a
slide.
Pre-soak
To soak film briefly in water prior to immersing it in developer.
Primary
colours
The set of colours that can be mixed to produce all the colours in
a colour space; in additive systems they are red, green, and blue,
while in subtractive systems they are cyan, magenta, and yellow.
Print
A positive picture, usually on paper, and usually produced from a
negative.
Printing
Frame
A device used for contact printing that holds a negative against the
photographic paper. The paper is exposed by light from an external
light source.
Printing-in
(See Burning-in)
Printer resolution
The amount of detail a printer or image-setter will reproduce, measured
in dots per inch (dpi).
Processing
Developing, fixing, and washing exposed photographic film or paper
to produce either a negative image or a positive image.
Process
colour
The four colour pigments cyan, magenta, yellow, and black used in
colour printing.
Program
Exposure
An exposure mode on an automatic or auto focus camera that automatically
sets both the aperture and the shutter speed for proper exposure.
Projected
Frame
See Finder, View Finder.
Pull
processing
Decreasing the effective speed of film, often to compensate for a
mistake in setting ISO. It is usually done by decreasing the development
time or the temperature of the developer.
Push
To expose film at a higher film speed rating than the normal, then
to compensate in part for the resulting underexposure by giving greater
development than normal. This permits shooting at a dimmer light level,
a faster shutter, or a smaller aperture that would otherwise be possible.
Push
Processing
Increasing the development time of a film to increase its effective
speed (raising the ISO number for initial exposure) for low-light
situations; forced development.
Rangefinder
A device included on many cameras as an aid in focusing.
Reflector
Any device used to reflect light onto a subject.
Reflected
Light
Light bounced off a subject, not falling on it (incident light).
Reciprocity
Most films are designed to be exposed within a certain range of exposure
times-usually between 1/15 second to 1/1000 second. When exposure
times fall outside of this range-becoming either significantly longer
or shorter-a film's characteristics may change. Loss of effective
film speed, contrast changes, and (with colour films) colour shifts
are the three common results. These changes are called reciprocity
effect.
Reciprocity
failure
In photographic emulsions occurs when exposure times fall outside
a films normal range. At these times an increase in exposure is required
in addition to the assessed amount. This can be achieved either by
increasing intensity or time.
Reciprocity
law
States that exposure = intensity x times, where intensity is equal
to the amount of light and time is equal to the time that amount of
light is allowed to act upon the photographic emulsion.
Recycling
time
Is the time it takes a flash unit to recharge between firings.
Red
eye
The appearance of deep red dots in the eyes of human and animal photographic
subjects. Redeye is is caused by the flash reflecting off the retina
in their eyes. It can be prevented by adjusting the camera angle,
being sure the subject does not look straight at the flash, or with
a redeye-reducing pre-flash. The pre-flash causes the subjects' pupils
to contract, reducing the visible retina and thus the possibility
of light reflecting from it.
Red-eye
Reduction Mode
A special flash mode whereby a pre-flash or a series of low-powered
flashes are emitted before the main flash goes off to expose the picture.
This causes the pupil in the human eye to close and helps eliminate
red-eye.
Reducers
Are solution which removes silver from negatives and prints. They
are used to diminish density and alter contrast on a photographic
emulsion.
Reducing
agent
Is a chemical in a developing solution which converts exposed silver
halides to black metallic silver.
Reflected
light reading
Is a measurement by a light meter of the amount of reflected light
being bounced off the subject. The light meter is pointed towards
the subject.
Refractive
index
Is a numerical value indicating the light bending power of a medium
such as glass. The greater the bending power, the greater the refractive
index.
Reflections
Are rays of light which strikes a surface and bounce back again. Specular
reflection occurs on even, polished surfaces; diffuse reflection occurs
on uneven surfaces, when light scatters.
Reflector
Any material or surface that reflects light. Reflectors are often
used in photography to soften the effect of the main light or to bounce
illumination into subjects shadows.
Refractive
index
Is a numerical value indicating the light bending power of a medium
such as glass. The greater the bending power, the greater the refractive
index.
Refresh
rate
The rate at which an image is redrawn on a CRT. This is needed because
the phosphors at each pixel are stimulated by the electron gun for
only a brief time. The faster the refresh rate, the more stable an
image will appear on the screen.
Registration
marks
Small crosshair on film used to align individual layers of film negatives.
Replenisher
A substance added to some types of developers after use to replace
exhausted chemicals so that the developer can be used again.
Resample
To change the resolution of an image. Re-sampling down discards pixel
information in an image; re-sampling up adds pixel information through
interpolation.
Resin
Coated Paper
Photographic paper with the emulsion coated in a resin (plastic).
Processing times are shorter than for other papers, but the paper
may not exhibit the same archival permanence of fibre based paper.
(See other paper types: variable contrast, graded contrast, fibre
based.)
Resolving
power
The resolving power of a lens is a measure of its ability to closely
spaced objects so they are recognizable as individual objects. It
is determined by photographing a series of closely spaced lines, measuring
the spacing between the most closely spaced lines that appear separate
on film. The resolving power is expressed as the number of lines pairs
per millimetre.
Resolution
The number of pixels per inch in an image, or the number of dots per
inch used by an output device.
Reticulation
Cracking or distorting of the emulsion during processing, usually
caused by wide temperature or chemical-activity differences between
the solutions.
Retouching
Altering a print or negative after development by use of dyes or pencils
to alter tones of highlights, shadows, and other details, or to remove
blemishes.
Reversal
A process for making a positive image directly from film exposed in
the camera; also for making a negative image directly from a negative
or a positive image from a positive transparency.
Reversal
film
Film that produces a positive image (transparency) on exposure and
development.
RGB
Red, green, and blue, the additive primaries; RGB is the basic additive
colour model used for colour video display, as on a computer monitor.
Rim-lighting
Lighting in which the subject appears outlined against a dark background.
Usually the light source is above and behind the subject, but rimlit
photographs can look quite different from conventional backlit images,
in which the background is usually bright.
Ring
flash
A circular-shaped electronic flash unit that fits around a lens and
provides shadowless, uniform frontal lighting, especially useful in
close-up photography.
Ring
light
A circular lamp or bundles of optical fibres arranged around the perimeter
of an objective lens to illuminate the object in the field below it.
A wide variety of sizes are available on both a stock and custom basis.
Rinse
Is a brief clean water wash between steps of a processing cycle to
reduce carry-over of one solution into another.
Rule
of thirds
A general composition guideline that divides the negative frame into
thirds horizontally and vertically to position the subject.
Safelight
An enclosed darkroom lamp fitted with a filter to screen out light
rays to which film and paper are sensitive.
Safety
film
A photographic film whose base is fire-resistant or slow burning.
At the present time, the terms "safety film" are synonymous.
Saturation
An attribute of perceived colour, or the percentage of hue in a colour.
Saturated colours are called vivid, strong, or deep. De-saturated
colours are called dull, weak, or washed out.
Screen
angle
The angle at which the halftone screens are placed in relation to
one another.
Screen frequency
The density of dots on the halftone screen, commonly measured in lines
per inch (lpi). Also known an screen ruling.
Selective
Focus
Choosing a lens opening that produces a shallow depth of field. Usually
this is used to isolate a subject by causing most other elements in
the scene to be blurred.
Self-timer
Mechanism delaying the opening of the shutter for some seconds after
the release has been operated. Also known as delayed action.
Sensitive
In photography, refers to materials that react to the actinic power
of light.
Sensitometer
An instrument with which a photographic emulsion is given a graduated
series of exposure to light of controlled spectral quality, intensity,
and duration. Depending upon whether the exposures vary in brightness
or duration, the instrument may be called an intensity scale or a
time scale sensitometer.
Sensitometry
Is the scientific study of the response of photographic materials
to exposure and development. It establishes emulsion speeds and recommended
development and processing times.
Shadow
Detail
Important dark areas (shadows) of a scene in which detail must be
recorded (exposed) onto the film. Shadows are represented on a negative
by sparse deposits of black metallic silver, reproducing as the dark
areas on a print. (Also see highlight separation.)
Sheet
film
Film that is cut into individual flat piece. Used in large format
view camera, with sizes like 4x5, 8x10 and 11x14 inches. Also called
cut film.
Shelf
life
Is the length of time unused material or chemicals will remain fresh.
Shift
Movement on large format camera ( or special " shift lens "
in other formats ) which can eliminate converging angles.
Shooting
distance
Refers to the distance between the subject and the film plane.
Shutter
Blades, a curtain, plate, or some other movable cover in a camera
that controls the time during which light reaches the film.
Shutter
Priority
An exposure mode on an automatic or auto focus camera that lets you
select the desired shutter speed; the camera sets the aperture for
proper exposure. If you change the shutter speed, or the light level
changes, the camera adjusts the aperture automatically.
Shutter
release
The mechanical or electromechanical button that releases the shutter
and takes the exposure.
Shutter
speeds
The duration that the shutter is held open during an exposure. A typical
range is from 1 full second to 1/1000 of a second. Combined with the
lens aperture it controls the total amount of exposure.
Side
lighting
Light striking the subject from the side relative to the position
of the camera; produces shadows and highlights to create modeling
on the subject.
Simple Camera
A camera that has few or no adjustments to be made by the picture-taker.
Usually, simple cameras have only one size of lens opening and one
or two shutter speeds and do not require focusing by the picture-taker.
Single-Lens-Reflex (SLR) Camera
A camera in which you view the scene through the same lens that takes
the picture.
Silhouette
A dark image outlined against a lighter background.
Silver
Halides
Generic name for a group of light sensitive compounds of silver combined
with a halogen, such as bromine, chlorine, iodine, or fluorine. Silver
halides change from white to black metallic silver when exposed to
light.
Skylight
filter
A UV filter with a pale rose tinge to it eliminate a blue colour cast
caused by haze, it may be kept in place permanently to protect the
lens from dust and scratching.
Slide
A transparency (often a positive image in colour) mounted between
glass or in a frame of cardboard or other material so that it may
be inserted into a projector.
Slide
film
Film used in making slides. Also known as " Transparency film
," " Positive film " or " Reversal film. "
Slow
film
Is film having an emulsion with low sensitivity to light. Typically
films having an ISO or 50 or less.
Slow
lens
Film which has a small maximum aperture. (i.e. f8 )
Snapshot
An informal photograph, especially one taken quickly by a simple,
hand-held camera.
Sodium
thiosulfate
The active ingredient in most fixer.
Soft
Developer
A paper developer that can be used alone or in combination with other
developers (two-bath development) to achieve more subtle contrast
control. Commonly used with graded papers to achieve intermediate
grades, that is, to soften the contrast.
(See paper types: variable contrast, graded contrast, resin coated,
fibre based.)
Soft
Focus
Produced by use of a special lens that creates soft outlines.
Soft Lighting
Lighting that is low or moderate in contrast, such as on an overcast
day.
Specular
highlight
A bright reflection from a light source containing little or no detail.
Specular
reflection
Light rays that are highly redirected at or near the same angle of
incidence to a surface. Observation at this angle allows the viewer
to "see" the light source.
Speed
A measure of the sensitivity to light of a photographic emulsion.
Spherical
aberration
Light passing through a convex lens will be brought to different focus
depending upon whether the light passes through near the centre of
the lens or closer to the periphery. Lens designers strive to correct
this kind of zonal aberration to bring peripheral and near-central
rays to a common focus.
Spotting
Retouching a processed print with a pencil or brush (with watercolours
or dyes) to eliminate spots left by dust or scratches on the negative.
Spotlight
Is an artificial light source using a fresnel lens, reflector, and
simple focusing system to produce a strong beam of light of controllable
width.
Spot meter
An exposure meter that measures the light reflected from a small area
of the subject Hand-held spot meters may measure an area as small
as one degree; those built into the camera may measure a somewhat
larger area.
Stabilizer
A processing solution used in colour processing to make the dyes produced
by development more stables.
Stain
Discoloured areas on film or paper. Usually caused by contaminated
developing solutions or by insufficient fixing, washing, or agitation.
Standard
lens
Lens with a focal length approximately equal to the diagonal of the
film format with which it is used. With 35mm this is usually 50mm.
Step
wedge
A printed series of density increases, in regular steps from transparent
to opaque. its a method of making exposure tests when enlarging.
Stock
Photos
An already existing picture that can be purchased for use instead
of having a photograph specifically made.
Stock
solution
A concentrated chemical solution that is diluted before use.
Stop Bath
An acid rinse, usually a weak solution of acetic acid, used as a second
step when developing black-and-white film or paper. It stops development
and makes the hypo (fixing bath) last longer.
Stopping
Down
Changing the lens aperture to a smaller opening; for example, from
f/8 to f/11.
Subtractive
colour
Combining cyan, magenta and yellow inks (or other colorants) to create
black; each ink subtracts from the white incident light, until nothing
is left except black.
Swing
back / front
term used to describe the movable lens and back panels of most view
and monorail cameras. They allow manipulation of perspective and depth
of field.
Sync
cord
An electrical cord connecting a flash unit with a camera so that the
two can be synchronized.
T (setting)
Setting that holds the camera shutter open until the shutter dial
is turned or release is press the second time. This setting differs
from " B" (Bulb) that is usually is a stand alone setting
and never drains the battery power and thus ideal for really long
time exposures.
Telephoto
Lens
A lens that makes a subject appear larger on film than does a normal
lens at the same camera-to-subject distance. A telephoto lens has
a longer focal length and narrower field of view than a normal lens.
Tempering
bath
Large tank or deep tray filled with water maintained at the correct
temperature for processing. Used to house tanks, drums or trays as
well as containers of processing solutions.
Test
Strip
A strip of printing paper that is given a series of incremental exposure
times (such as 3, 6, 9, 12 seconds) in order to determine the ideal
base exposure time.
T-Grain
technology
Trademark for patented Kodak film emulsion technology.
Thin
Negative
A negative that is underexposed or underdeveloped (or both). A thin
negative appears less dense than a normal negative.
Threaded
lens
Some cameras, such as compact cameras, allow the addition of additional
lenses to increase the telephoto range or allow greater magnification
for macro work. The most convenient way to add these accessory lenses
is by means of a threaded lens. The end of the lens housing has threads
that these other lens can thread into, which an adapter can be attached
to accept the accessory lenses.
Through-The-Lens
Focusing
Viewing a scene to be photographed through the same lens that admits
light to the film. Through-the-lens viewing, as in a single-lens-reflex
(SLR) camera, while focusing and composing a picture, eliminates parallax.
Through-The-Lens Metering
Meter built into the camera determines exposure for the scene by reading
light that passes through the lens during picture-taking.
Thumbnails
Miniature pictures, resembling slides, that the Light-Box catalog
displays. Each thumbnail contains specific information for each image
that comes with Photo-Disc.
TIFF
Tagged Image File Format, a file format for exchanging bitmapped and
grayscale images among applications.
Time
Exposure
A comparatively long exposure made in seconds or minutes.
Tint
Shades of white in a finished print, controlled by the colour of the
paper, varying from white to buff.
Tone
The degree of lightness or darkness in any given area of a print;
also referred to as value. Cold tones (bluish) and warm tones (reddish)
refer to the colour of the image in both black-and-white and colour
photographs. A black and white photograph is made up of a series of
grey tones. Controlling these tones allows us to control the nature
of the photograph, both emotionally and technically. Since the number
of grey tones is so large it needs to be broken down from a continuous
range to a series of distinct zones. These zones make up what is known
as the Zone System.
Tonal
Values, Tonal Range
The range of tone (zones) within a particular area or scene.
Toning
Intensifying or changing the tone of a photographic print after processing.
Solutions called toners are used to produce various shades of colours.
Soaking the print in selenium to help darken the black areas and give
the print an overall feeling of "richness". Other tonal
techniques include burning, dodging, flashing, and bleaching.
Transmitted
Light
Light which is passed through a transparent or translucent medium.
Transparency
A positive photographic image on film; viewed or projected by transmitted
light (light shining through film).
Transparent
magnetic layer
Information storage layer built into Advanced Photo System film that
enables enhanced information exchange capabilities, improving print
quality by capturing lighting and scene information and other picture-taking
data; basis for future information exchange features.
Tripod
A three-legged supporting stand used to hold the camera steady. Especially
useful when using slow shutter speeds and/or telephoto lenses.
TTL
flash
Through the lens ( TTL ) automatic flash output control uses a light
sensor that measures the flash intensity through the lens, as reflected
by the subject on the film, then shuts off the flash when the measurement
indicates a correct exposure.
Tungsten
Light
Light from regular room lamps and ceiling fixtures, not fluorescent.
Two-Bath
Development
The use of two different developers to alter the contrast in a print.
(See soft developer, hard developer.)
Type
A film
Colour film balance to produce accurate colour renditions when the
light source that illuminates the scene, has a colour temperature
of about 3400K as does a photoflood.
Type
B film
See tungsten film.
Ultraviolet
The part of the spectrum just beyond violet. Ultraviolet light is
invisible to the human eye but strongly affects photographic materials.
Under-development
Is a reduction in the degree of development. It is usually caused
by shortened development time or a decrease in the temperature of
the solution. It results in a loss of density and a reduction in image
contrast.
Underexposure
A condition in which too little light reaches the film, producing
a thin negative, a dark slide, or a muddy-looking print.
Unicode
or Monopod.
A one-legged support used to hold the camera steady.
UV
filter
Is a filter which is used to absorb ultraviolet (UV) radiation.
Vacuum
back
Is a camera back with a perforated plate through which air is drawn
by a pump. A sheet of film is therefore sucked flat against the plate
and held firmly during exposure used for special large format cameras
such as copying devices where dimensional accuracy is critical.
Vacuum
easel
Is a compact printing frame which ensures firm contact between the
film and paper by excluding air between the surfaces. Some types are
used to hold up the paper flat on the enlarger baseboard when enlarging.
Value
A measure from white to black, the higher the value, the darker the
image.
Vapour
lamp
A lamp containing a gas or vapour that glows with light when an electric
current passes through it. Mercury, neon and sodium vapour lamps produce
strongly coloured light. The light from fluorescent tubes is closer
to daylight.
Vanishing
point
Is the point at which parallel lines, viewed obliquely, appear to
converge in the distance.
Variable-Contrast
Paper
Photographic paper that provides different grades of contrast when
exposed through special filters.
View
camera
Is a large format camera which has a ground glass screen at the image
plane for viewing and focusing.
Viewfinder
(See Finder)
Vignette
A fall-off in brightness at the edges of an image or print. Can be
caused by poor lens design. Using a lens hood not matched to the lens.
Attaching too many filters to the front of the lens.
Vignetting
Is a printing technique where the edges of the picture are gradually
faded out to black or white. It also refers to a fall off in illumination
at the edges of an image, such as may be caused by a lens hood or
similar attachment partially blocking the field of view of the lens.
Visible
light
The portion of the electromagnetic spectrum that the human eye can
see.
Wide-Angle Lens
A lens that has a shorter focal length, and a wider field of view,
than a standard lens.
Working
(strength) Solution
Diluted photographic chemicals ready for use. These tend to be 'one-shot'
i.e. use then throw away. Some, such as fixers, some toners, stop
baths etc can be re-used.
Zoom Lens
A lens in which the focal length can be altered. In effect, this gives
you lenses of many focal lengths.
Zone
System
Invented by Ansel Adams and Fred Archer in the 1940's, the Zone System
is a means of making an exposure in a scientifically accurate manner.
The Zone system breaks the black and white tones into 10 zones or
"scales" ranging from complete black with no visible texture
(Zone I) to pure white with no visible texture (Zone X). Zone V is
the middle grey tone. The Zone System of Exposure is widely used today.
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