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840 terms · page 6 of 35


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All A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0–9
Files, Metadata & Workflow

Checksum Verification

Computing a mathematical fingerprint of a file and comparing it later to confirm the data has not changed.

hash
Colour & Colour Management

Chroma

The colourfulness of an area judged relative to the brightness of a similarly lit white, a perceptually defined counterpart to saturation.

C* (CIELAB)
Files, Metadata & Workflow

Chroma Subsampling

A compression technique that records colour information at lower resolution than brightness information.

4:4:4, 4:2:2, 4:2:0 ratio
Post-Processing & Retouching

Chromatic Aberration Removal

Processing that eliminates coloured fringing along high-contrast edges by realigning or desaturating the offending channels.

px
Colour & Colour Management

Chromatic Adaptation

The visual system's automatic adjustment to the colour of the prevailing light, which keeps familiar objects looking the same colour under…

Film, Darkroom & Historic Processes

Chromogenic Black and White Film

A monochrome film that forms its image from dye couplers rather than silver, and is processed in standard colour chemistry.

ISO
Printing, Display & Output

Chromogenic Print

A print made on light-sensitive photographic paper and developed in chemistry, whether exposed from a negative or by a digital light source.

Colour & Colour Management

CIE Chromaticity Diagram

The horseshoe-shaped plot of all colours visible to human vision, on which colour space gamuts are drawn as triangles.

CIE xy
Colour & Colour Management

CIELAB

A device-independent colour model with one lightness axis and two opponent colour axes, designed so equal numerical steps look equally…

ΔE = √(ΔL*² + Δa*² + Δb*²) L*a*b*
Motion, Video & Creative Techniques

Cinemagraph

A still image in which a small isolated area moves in a seamless loop.

seconds
Focus & Depth of Field

Circle of Confusion

The largest blur circle that still reads as a point to the viewer, and the value on which every depth-of-field calculation depends.

c ≈ diagonal / 1500 mm
Optics, Lenses & Filters

Circular Polarising Filter

A rotating filter that blocks polarised light, cutting reflections from non-metallic surfaces and deepening blue skies.

Effect peak at 90° from the sun stops (EV)
Lighting & Flash

Clamshell Lighting

A beauty setup with one soft source above the face and a reflector or second source directly below, both facing the subject.

Post-Processing & Retouching

Clarity

A midtone local-contrast control that adds apparent punch and definition without affecting the extreme tones.

%
Exposure & Metering

Clipping

The loss of tonal information when values are pushed past the maximum or minimum a file can encode.

Post-Processing & Retouching

Clipping Mask

A layer restricted so that it only affects the single layer directly beneath it, using that layer's shape as its boundary.

Post-Processing & Retouching

Clone Stamp

A retouching tool that copies pixels from one part of an image directly onto another.

px (brush size)
Optics, Lenses & Filters

Close-up Diopter

A magnifying filter that screws onto the front of a lens to allow closer focusing without losing light.

Working distance = 1000 / diopter power (mm) diopters
Files, Metadata & Workflow

Cloud Backup

Storing a copy of image files on remote servers accessed over the internet.

TB
Sensors & Digital Capture

CMOS Sensor

A sensor type in which each photosite has its own amplifier and the charge is converted to voltage at the pixel itself.

Printing, Display & Output

CMYK

The subtractive four-ink model — cyan, magenta, yellow and black — used in commercial printing.

%
Motion, Video & Creative Techniques

Codec

The compression scheme used to encode and decode video data.

Files, Metadata & Workflow

Collection

A named grouping of images assembled for a purpose, independent of where the files are stored.

count
Colour & Colour Management

Colorimeter

An instrument that measures colour through three filters approximating human vision, used mainly for calibrating displays.