Basic Photography Course

ANGLE OF ACCEPTANCE

The angle that objects

must align within to affect the reading of a
photoelectric exposure meter.

ANGLE OF FIELD

A property of a lens. The angle

subtended by the lines that pass through the center
of the lens and locate the diameter of the maximum
image area within the specified definition of the
lens. Also called angular fields.

ANHYDROUS

Dry, containing no water of

crystallization.

ANTICURL BACKING

A transparent, gelatin

coating sometimes applied to the opposite side of a
photographic film from the emulsion to prevent
curling by balancing the forces that tend to curl the
film, as it is wet and dried during processing.

ANTIHALATION COATING

A lightabsorbing

coating applied to the back side of the support of a
film or plate, or between the emulsion and the
support, to suppress halation (also called

antihalation backing). See HALATION.

ANTISLUDGE AGENT

A chemical compound

added to photographic processing solutions to
prevent the formation of sludge. Sodium
metaphosphate and boric acid are commonly used
for this purpose.

APERTURE

In an optical system, an opening through

which light can pass.

APERTURE, CURTAIN

The slit in a focalplane

shutter that permits light to reach the film. The slit
size may be either fixed or variable.

ARTIFICIAL LIGHT

Illumination provided by

incandescent, fluorescent, or flame sources.

ASPECT RATIO

The ratio of the height to the width

of the film or television frame; that is, three units
high to four units wide (3:4).

ASTIGMATISM

A lens aberration that causes an

offaxis point to be imaged as a pair of lines at right

angles to each other and in different focal planes. A
lens having astigmatism is unable to image
horizontal and vertical lines in the same plane with
equal sharpness.

ATMOSPHERIC PERSPECTIVE

Applied to the

effect of distance created by atmospheric haze in a
photograph. It lightens the tones as the distance

increases.

AUDIO TRACK

The area of the videotape that is used

for recording audio information.

AUTO IRIS

An automatic control of the lens

diaphragm.

AUTOFOCUS

A feature of certain cameras or

enlargers by which the image is kept in focus
automatically regardless of the degree of reduction
or magnification.

AVOIRDUPOIS

The system of weights commonly

used in the United States and the British Empire in
which the primary unit is the pound (7,000 grains);
usually expressed in pounds, ounces, and binary
fractions thereof.

BACK LIGHT

Illumination from behind the subject

in a direction substantially parallel to a vertical
plane through the optical axis of the camera.

BACKGROUND

(1) That part of the landscape which

is more distant than the principal object from the
camera. (2) A screen, drape, or projected scene used
in a photography studio behind the subject.

BACKING PAPER (ROLL FILM)

The protective

strip of paper to which the film is attached. Backing
paper is usually black on one side and colored on
the opposite side. Numerals are usually printed on
the colored side in a position where they can be
viewed through the camera window. Also called
duplex paper. (ASA)

BARN DOOR

Folding wings used in front of studio

spotlights to aid in directing the light and to shade
portions of the subject from direct illumination.

BASE DENSITY

The density of a film base. No plastic

is 100% transparent, so all films have some base
density.

BATH

Any chemical solution used in processing

photographic materials.

BEAM SPLITTER

An optical system so arranged as

to reflect or transmit two or more portions of a light
beam along different optical paths.

BELLOWS

The extensible lightproof device that joins

the lens board to the film support section of a
camera

BLEACH, PHOTOGRAPHIC

(1) To remove an

image from a photographic film. Especially to do
this by converting a metallic silver image to a halide
or other salt that can be removed from the film with
hypo. When bleaching is not carried to completion,

it is called reducing. (2) Any chemical reagent that
can be used for bleaching. (3) Any chemical solution

used for bleaching.

AI-2

contents

Basic Photography Course

<- previous page

next page ->


DOFMaster for Windows On-line Depth of Field Calculator DOFMaster for Mobile Devices On-line Depth of Field Table Hyperfocal Distance Chart Articles FAQ Recommended Books Support Contact Links Home As an Amazon Associate I earn from qualifying purchases.	contents <- previous page next page -> ANGLE OF ACCEPTANCE The angle that objects must align within to affect the reading of a photoelectric exposure meter. ANGLE OF FIELD A property of a lens. The angle subtended by the lines that pass through the center of the lens and locate the diameter of the maximum image area within the specified definition of the lens. Also called angular fields. ANHYDROUS Dry, containing no water of crystallization. ANTICURL BACKING A transparent, gelatin coating sometimes applied to the opposite side of a photographic film from the emulsion to prevent curling by balancing the forces that tend to curl the film, as it is wet and dried during processing. ANTIHALATION COATING A lightabsorbing coating applied to the back side of the support of a film or plate, or between the emulsion and the support, to suppress halation (also called antihalation backing). See HALATION. ANTISLUDGE AGENT A chemical compound added to photographic processing solutions to prevent the formation of sludge. Sodium metaphosphate and boric acid are commonly used for this purpose. APERTURE In an optical system, an opening through which light can pass. APERTURE, CURTAIN The slit in a focalplane shutter that permits light to reach the film. The slit size may be either fixed or variable. ARTIFICIAL LIGHT Illumination provided by incandescent, fluorescent, or flame sources. ASPECT RATIO The ratio of the height to the width of the film or television frame; that is, three units high to four units wide (3:4). ASTIGMATISM A lens aberration that causes an offaxis point to be imaged as a pair of lines at right angles to each other and in different focal planes. A lens having astigmatism is unable to image horizontal and vertical lines in the same plane with equal sharpness. ATMOSPHERIC PERSPECTIVE Applied to the effect of distance created by atmospheric haze in a photograph. It lightens the tones as the distance increases. AUDIO TRACK The area of the videotape that is used for recording audio information. AUTO IRIS An automatic control of the lens diaphragm. AUTOFOCUS A feature of certain cameras or enlargers by which the image is kept in focus automatically regardless of the degree of reduction or magnification. AVOIRDUPOIS The system of weights commonly used in the United States and the British Empire in which the primary unit is the pound (7,000 grains); usually expressed in pounds, ounces, and binary fractions thereof. BACK LIGHT Illumination from behind the subject in a direction substantially parallel to a vertical plane through the optical axis of the camera. BACKGROUND (1) That part of the landscape which is more distant than the principal object from the camera. (2) A screen, drape, or projected scene used in a photography studio behind the subject. BACKING PAPER (ROLL FILM) The protective strip of paper to which the film is attached. Backing paper is usually black on one side and colored on the opposite side. Numerals are usually printed on the colored side in a position where they can be viewed through the camera window. Also called duplex paper. (ASA) BARN DOOR Folding wings used in front of studio spotlights to aid in directing the light and to shade portions of the subject from direct illumination. BASE DENSITY The density of a film base. No plastic is 100% transparent, so all films have some base density. BATH Any chemical solution used in processing photographic materials. BEAM SPLITTER An optical system so arranged as to reflect or transmit two or more portions of a light beam along different optical paths. BELLOWS The extensible lightproof device that joins the lens board to the film support section of a camera BLEACH, PHOTOGRAPHIC (1) To remove an image from a photographic film. Especially to do this by converting a metallic silver image to a halide or other salt that can be removed from the film with hypo. When bleaching is not carried to completion, it is called reducing. (2) Any chemical reagent that can be used for bleaching. (3) Any chemical solution used for bleaching. AI-2 contents Basic Photography Course <- previous page next page ->	As an Amazon Associate I earn from qualifying purchases.
	WWW.DOFMASTER.COM © 2006 Don Fleming. All rights reserved.