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Glossary of Terms Aperture "The size of the lens opening through which light passes".(1) Also called F- stops; they refer to the series of indicated click stops normally found on the lens as a sequence of numbers, such as F- 2.8, 4, 5.6, 8, 11, and 16. When the size of the aperture is reduced, the designated number is higher. When the size of the aperture is increased, the designated number is lower. Depending upon the camera, the aperture is controlled either manually or automatically.
Taken from, Barbara London
Upton with John Upton, Photography Bracket To make more than one exposure, usually deviating one half to one full stop over and under the recommended exposure. Bracketing allows the photographer to choose from several exposures in order to select the best exposure, which may not necessarily be the "correct" one.
Built-in
meter
An exposure meter built
into a camera, allowing the photographer to take reflected light readings
directly from the camera. Color
conversion filter When using
color film that is not compatible with a given light source, a color
conversion filter can be used to adapt the film to the light source.
The most common conversion filters are used when shooting daylight film
under tungsten light (80A), or tungsten film in daylight (85B). For
example, daylight color slide film shot under tungsten without a conversion
filter will have a warm yellowish cast. By using the 80A blue filter,
the photographs will have color that is more true to life. Compact
Flash Memory Card Compression Ratio Continuous
tone
A way to describe an image
with a range of tones from black through gray to white. Contrast
"The difference in darkness
or density between one tone and another"(2),
often used to describe the difference in brightness between the darkest
and lightest areas of an image or a scene. Correction filter
A color filter, which when
used with black & white film, produces tones of the same relative
brightness as the eye sees them. For example, a K2 yellow filter with
black & white film, will darken a blue sky so it does not appear to
be too bright or washed out. Daylight
film "Color film balanced to
produce accurate color renditions when the light source illuminating
the photographed scene has a color temperature of about 5500K, such
as in midday sunlight".(3)
This type of film is also compatible with electronic flash and blue
flashbulbs, as well as daylight balanced flourescent lamps, such as
the copystand lamps in B-19 Sibley. Diopter Optically, a unit of measurement of the refractive power of lenses. Refractive in this case, refers to the ability of the eye to bend light so that an image can be brought into focus.(10) In photography, diopter is a term used to describe the focusing power of a supplementary or close up lens. The Nikon D-1 has a diopter that will adjust to the camera user's own eye, using a control button on the camera body viewfinder. E-6
E-6 is a seven step chemical process for developing
"Ektachrome", "Fujichrome" and other brands of color slide film. E-6
processing is available at most photo stores as well as in kit form
for those who wish to process their own slides. Exposure Compensation This feature is used when a scene contains stark lighting contrasts or extremely bright or dimly lit subjects. Exposure compensation is adjusted in increments called values. Adjustment is made in values as small as one third value, with a range of plus 5 to minus 5 from the optimum exposure.(15) Figure
ground
"To see parts of a visual
field as solid, well defined objects standing out against a less distinct
background."(4)
Fill
flash
When photographing in bright
sunlight, especially with the sun behind or at an angle to the subject,
harsh shadows on faces and other important features can be softened and
lightened by using a fill flash. This technique is also useful when shooting
subjects in the shade on sunny days. In both examples, by exposing for
the bright areas of a scene, and using the flash to fill in the darker
shadows or foreground, a more pleasing balance of light is created. Film
speed
"The relative sensitivity
to light of a film"(5).
For example, the difference in sensitivity between 100 speed film and
400 speed film is equal to two full stops of exposure. Thus, 400 speed
film is three times as sensitive to light as 100 speed film. F-stop The common term for the aperture setting (f-number) of a lens; the f-number is equal to the focal length of a lens divided by the diameter of the aperture.(6). The f-stop, shutter speed combinations illustrated below are examples of reciprocal exposure equivalents:
Derived from, Barbara
London Upton with John Upton, Photography Gain Grain
The massing of the silver
particles in a photographic emulsion that produces a coarse or speckled
look in a picture, particularly noticeable in more uniform tones. Generally,
the faster the film the more visible its grain. Gray
card Image Stabilizer The image stabilizer can compensate for a wide range of camera movement, allowing the user to make steady recordings even at high magnification with little loss of picture quality.(16) Iris Same as aperture. ISO/ASA Settings Numerical ratings that describe a film's sensitivity to light. The numbers double as the film's sensitivity doubles. ISO (International Standards Organization) and ASA (American Standards Association), are equivalent. Kelvin
temperature Generally referred
to as color temperature, the scale used by photographers to measure
the warmth or coolness of light. The color of a light source is specified
as degrees in Kelvin. The scale is expressed as a range of temperature
from about 1000 K (firelight), to 10,000 K (clear blue afternoon sky)
& beyond. In general photographic applications, the most commonly
used color temperatures are 3200 K, (tungsten), and 5500-6000 K, (daylight).
LCD The LCD of a digital camera is the screen used to review, preview and even act as a large size viewfinder. Many consumer digital cameras allow you to use the LCD to frame the scene providing a live video feed of the image to be captured. The LCD screen is also used to review images taken and change camera settings Macro In strict photographic terms the word Macro means the optical ability to produce a 1:1 or higher magnification of an object on the film negative, that is get very close (not always physically) to a very small object (a bit like a microscope does, but obviously not as much). The second type of lens is a close-up lens, normally anything less than 1:2 is seen as close-up (rather than Macro). Matrix Metering Camera metering performed by a sensor which sets the exposure using data from all areas of the picture frame. Mini DV Cassette Stands for Mini Digital Video Cassette. Monochrome Image Refers to an image in tones of black & white or different shades of one color.(9) ND Filter Neutral density filter. A filter that absorbs some of the light passing through the camera lens. Programmed Auto Exposure In "programmed auto" exposure mode, the camera automatically sets the aperture and shutter speed to produce the best result. Resolution
The degree to which an image
is distinct in its details as a function of the spacing of individual
optical elements, such as the grain of a light sensitive emulsion.(7)
Resolving power is expressed in lines per millimeter. High resolution
Films have a greater number of lines per millimeter. Sensitivity In conventional analog photography, film sensitivity doubles as the ISO/ASA value doubles. Similarly, in digital photography, ISO/ASA sensitivity is calibrated and expressed as camera sensitivity using the same arbitrary settings, i.e. 100, 200, 400, 800 etc. Shutter speed The calibrated length of time of exposure. Shutter speed controls the amount of light that reaches the film during exposure. Like the aperture it is a variable that is controlled either mechanically by the photographer or electronically by the camera itself. The f-stop, shutter speed combinations illustrated below are examples of reciprical exposure equivalents:
Derived from,
Barbara London Upton with John Upton, Photography Single Servo Auto Focus A feedback mechanism in the camera that controls the auto focus function.(12) Specifically, in single servo A.F. mode the camera focuses on a still object and locks the focus on that object when the shutter release button is depressed half way. In continuous servo A.F., the camera focuses continuously when the shutter release button is depressed half way. In this mode the camera's auto focus mechanism tracks anything moving in the frame. (13) Slow Sync. Flash Setting Slow synchronization allows for a longer exposure time, creating a more even exposure balance between the flash exposure and ambient lighting. Tungsten
film
Color film balanced to give
accurate color renditions when using a light source of about 3200 K -
3400 K.(8)
Tungsten film is used with normal incandescent type light bulbs
or photo flood lamps. Waist
level finder White Balance In digital photography white balance refers to the camera's ability to adjust the color of light, indoors or outdoors, natural or artificial, so that the colors which make up white, when viewed in the final image, are true to the original scene. (11) XGA & VGA image size XGA & VGA are image display standards which represent image size. Because these image size settings contain the fewest number of pixels, ( XGA = 1024 x 768 & VGA = 640 X 480 pixels ) they also yield the lowest quality image. Conversely, XGA & VGA sizes allow for the greatest number of images that can be stored in the memory card. Back to Visual Resources Facility 1. Barbara London Upton with John Upton, Photography (Glenview, Ill.: Scott, Foresman &Co., Fourth Edition, 1989), 413. 4. Francis D.K. Ching, A Visual Dictionary of Architecture(New York, N.Y.:Van Nostrand Reinhold, 1997), 265. 6. Derived from: Upton, Photography 415. 7. Derived from: The Getty Art History Information Program, Art & Architecture Thesaurus, Second Edition, Vol. Five(Oxford, Oxford University Press,1994)117. 8.
Derived from: Upton, Photography 418. 
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