Glossary

acid A substance with a pH below 7 that neutralizes alkalies.
air gun See dust gun.
alkali A substance with a pH above 7. The reagent in Polaroid 600 and Spectra films are alkaline solutions.
AE See Automatic Exposure.
AF See Automatic Focus.
aperture The size of the lens opening light passes through. The relative aperture is measured as the focal length of the lens divided by the diameter of the lens, which is expressed as an f-number: f/5, f/8 and so on.
archival 1. a material that has been created and handled in a manner that will assist it in keeping it's original form for a long period of time. 2. a level of quality that will not harm or effect another material in premature deterioration.
artificial light Light from an electric lamp, a flash bulb or an electronic flash. It often describes light a photographer has to set up to illuminate a scene.
ASA A film speed similar to an ISO rating.
automatic exposure A camera operation in which the camera adjusts the shutter speed, the aperture or both to produce the correct exposure. Abbreviated AE.
automatic flash An electronic flash unit with a built-in meter that measures the light reflected back from the subject and terminates the flash when the exposure is correct.
automatic focus A system by which the camera adjusts its lens to focus on a given area. Abbreviated AF.
brayer A roller used by printers to manually apply ink.
brightness A subjunctive impression of the lightness of an object.
built-in meter A reflected-light exposure meter built into a camera or automatic flash so that light readings can be made directly from the camera's position.
cartridge A light-tight container that usually holds 10 pieces of film.
changing bag A light-tight bag that a photographer can insert his or her hands to handle film when a darkroom is not available.
chemistry The chemical composition of a substance.
chemistry pod The small container that holds the reagent chemistry necessary to process instant integral films.
close-up A larger-than-normal image made by focusing the subject closer than normal to the lens with the use of supplementary lenses or extension tubes.
close-up lens A supplementary lens that allows a photographer to photograph a subject at a close distance.
color balance A film's response to the colors of a subject. Color films are balanced for use with specific light sources.
color correction Correcting or changing the color information in a photograph.
contact printing The process of placing a negative in contact with light-sensitive material and passing light through the transparency onto the light-sensitive material making a photograph with a 1:1 ratio.
contact printing easel An easel used to hold both the transparency and the film to make a contact pint.
contrast The difference in darkness or density between tones.
darkroom A room sufficiently dark to handle light-sensitive materials without causing accidental exposure.
cool Describes blue-based colors that by association with common objects (water, ice, and so on) give the impression of coolness. Opposite: warm.
daylight film Color film that is balanced to accurately reproduce color when the light source illuminating the photographed scene has a color temperature of 5500K.
double exposure An image in which the light-sensitive material has been exposed twice.
dark slide See protective sheet.
dry mount To attach a print to another surface by placing a sheet of dry-mount tissue between the print and the mounting surface. This sandwich is placed in a heated mounting press to melt an adhesive in the tissue.
dust gun A container filled with compressed air used to blow dust particles and other small debris off of a surface. Also called an air gun.
emulsion A light-sensitive coating applied to photographic films or papers made of silver halide crystals and other chemicals.
enlarger An optical instrument ordinarily used to project a transparent image onto sensitized paper to create photographic prints.
existing light Light that already exists where a subject is to be photographed. Often implies a relatively dim light.
exposure 1. The act of letting light fall onto a light-sensitive material. 2. The amount of light reaching the light-sensitive material multiplied by the length of time it falls on the material.
fast A film that is very sensitive to light. Opposite: slow.
fiber board A stiff sheet or board made by compressing fibers.
film The light-sensitive material used in a camera to record a photographic image.
film speed The relative sensitivity to light of a film. Film speed ratings increase as the sensitivity of the film increases.
filter A piece of colored glass, plastic or other material that absorbs some of the wavelengths of light passing through it depending on what wavelengths it was designed to absorb.
f-number A number that equals the focal length of a lens divided by the diameter of the aperture at the same setting. Also called f-stop.
focal length The distance from the lens to the focal plane when the lens is focused on infinity. The longer the focal length is, the grater the magnification of the image and the smaller the angle of view.
fog An overall density in the photographic image usually caused by accidental exposure to light.
frame 1. The edges of an image. 2. A (usually) square or rectangular case used to house a mat with an image in it.
f-stop The common term for the aperture of a lens. See also f-number.
glossy Describes a surface with a great deal of sheen. Opposite: matte.
gray scale A series of tones ranging from black to white through intermediate shades of gray.
hue Color or the gradation of.
incandescent light See tungsten light.
instant integral film A film that contains the chemicals needed to develop an image automatically after exposure without the need for darkroom development. Such film is meant to hold the photographic image, the negative and the chemistry after processing.
lens A piece or several pieces of optical glass used to focus an image of a subject.
light meter An instrument that measures either the amount of light falling on a subject or the amount of light reflected or emitted by a subject which is used to determine the aperture and shutter speed settings for the correct exposure.
light-tight Describes something that is protected by opaque material that does not allow light to pass through it.
macro Describes 1. a photograph that has a 1:1 ratio with its subject. 2. a lens capable of producing a photograph at a 1:1 ratio.
manipulate To treat or operate either with the hands or by mechanical means in a skillful manner.
manual Controlled or done by hand and not by machine.
mat A piece of cardboard with an opening cut in it that is placed over a print shaped to fit into a frame.
mat knife A short knife or blade in a large, easy-to-hold handle used for cutting mats.
matte Describes a surface with a relatively dull, non-reflective surface. Opposite: glossy.
metering system See built-in meter.
multiple exposure An image in which the light-sensitive material has been exposed more than once.
mylar See polyester film.
nm Abbreviation for nanometer. See nanometer.
nanometer A unit commonly used for measuring wavelengths of light. one billionth or 10-9 of a meter.
negative Any image with tones that are the reverse of those in the subject. Opposite: positive.
neutral density filter A filter which reduces the amount of light passing through the lens without otherwise changing it.
open up To increase the size of a lens aperture. Opposite: stop down.
overexpose To give more than the normal exposure to light-sensitive materials, resulting in a silver density that is often too great for best results. Opposite: underexposure.
paper safe A light-tight box used to store light-sensitive materials to protect them from accidental exposure.
photogram An photographic image formed by placing objects directly onto a sheet of light-sensitive material then exposing the material to light.
polyester casing The outer shell of an integral photograph that encloses it and holds it together as one unit.
polyester film 1. a thin, transparent sheet of plastic used to view the photographic image of a Polaroid integral photograph through. 2. a base for the image receiving layer of a Polaroid integral photograph.
positive Any image with tones that are the representative of those in the subject. Opposite: negative.
protective sheet A protective cover that is removed from a sheet film holder or cartridge when film in the holder is to be exposed. Also called dark slide.
reciprocity law The theoretical relationship between length of exposure and intensity of light, stating that an increase in one will be balanced by a decrease in the other. The law does not hold true for very long or very short exposures.
reciprocity failure Describes the failure of the law of reciprocity. This failure causes underexposure unless the exposure is increased. It also causes color shifts in color materials. Also called reciprocity effect.
residue A thin coating of a substance that remains after the completion of a process or the removal of a chemical.
reverse relief A term generally used to describe sculpture when the foreground is recessed and the background is raised.
SLR See single lens reflex.
sandwich Two images placed in contact with one another to produce a new image.
shutter A mechanism that opens and closes to admit light into a camera to expose the film held in the camera for a measured length of time.
single lens reflex A camera in which the image formed by the lens is reflected by a mirror onto a ground-glass screen for viewing through the viewfinder or rangefinder. The mirror swings out of the way just before exposure to let the image reach the film. Abbreviated SLR.
slide A transparency (usually a positive image) mounted between glass or in a frame of cardboard or other material so that it may be inserted into an enlarger or projector.
spot To apply a dye or pigment over blemishes to correct them.
stop 1. An aperture setting on a lens. See f-stop. 2. A change in exposure by a factor of two. One stop more exposure doubles the light reaching the light-sensitive material. Either the aperture or the exposure time can be changed. 3. See stop down.
stop down To decrease the size of the lens aperture. Opposite: open up.
tone The lightness or darkness of a particular area. A highlight can also be called a light tone; a shadow can also be called a dark tone.
transparency An image on a transparent base, such as acetate or polyester that is viewed by light passing through it as opposed to light reflecting off of it. See slide.
tungsten light Light from ordinary light bulbs containing a thin wire that emits light when an electrical current passes along it. Also called incandescent light.
UV See ultraviolet.
ultraviolet The part of the spectrum just beyond violet. Ultraviolet light is invisible to the human eye but strongly affects most photographic materials.
underexpose To give less than normal exposure to light-sensitive material, resulting in a silver density that is often less than necessary for best results. Opposite: overexposure.
viewfinder A small window on a camera through which the subject is seen and framed.
viewing lens The lens on a camera through which the photographer views the subject.
warm Describes red-based colors that by association with common objects (fire, sun, and so on) give the impression of warmth. Opposite: cool.
wavelength The distance in the line of advance of a wave from any one point to the next point of corresponding phase. When a wavelength is within the visible spectrum it is known as visible light.
wetting agent A chemical solution used after washing film that reduces the surface tension of the water remaining on the film, which speeds the drying and helps prevent water spots.yellowing A phenomenon common to Polaroid instant integral photographs when they are left in dark storage. The image develops an undesired yellow tint.

Contents © 1995-2009 J. Norris unless otherwise noted. All rights reserved.