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840 terms · page 16 of 35


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Composition & Visual Design

Golden Spiral

A logarithmic spiral constructed from golden-ratio rectangles, sometimes overlaid on a frame as a compositional guide.

r = ae^(bθ)
Composition & Visual Design

Golden Triangle

A compositional grid formed by a diagonal across the frame and two perpendicular lines from the remaining corners.

Post-Processing & Retouching

Gradient Mask

A mask that fades an adjustment smoothly along a linear direction, digitally imitating a graduated filter.

Optics, Lenses & Filters

Graduated Neutral Density Filter

A filter that is dark at one end and clear at the other, used to hold back a bright sky while leaving the land unaffected.

stops (EV)
Exposure & Metering

Grey Card

A physical card of known neutral 18 per cent reflectance, held in the subject's light to give both a reliable exposure reading and a white…

% reflectance
Genres, Movements & Theory

Group f/64

A short-lived association of West Coast American photographers formed in 1932 to advocate sharp, unmanipulated photography.

Lighting & Flash

Guide Number

A measure of a flash's power, equal to the product of the correct aperture and the subject distance at a stated ISO.

GN = N × d m at ISO 100
Cameras, Formats & Systems

Half-frame Format

A 35 mm format using an 18 by 24 millimetre vertical frame, doubling the number of exposures on a roll.

mm
Printing, Display & Output

Halftone

The reproduction of continuous tone by a grid of dots that vary in size, creating the impression of shades from a single ink.

lpi
Exposure & Metering

Handheld Light Meter

A separate instrument for measuring incident, reflected or flash light independently of the camera.

EV, f-stops
Lighting & Flash

Hard Light

Light from a source that is small relative to the subject, producing sharply defined shadows with abrupt edges.

Printing, Display & Output

Hard Proof

A physical test print made to verify colour and tone before committing to a final print run.

Printing, Display & Output

HDR Display

A screen capable of much higher peak brightness and contrast than conventional displays, showing a wider range of tones.

cd/m²
Post-Processing & Retouching

HDR Merge

Combining bracketed exposures into one file holding a greater dynamic range than any single frame could.

stops
Composition & Visual Design

Headroom

The space between the top of a subject's head and the upper edge of the frame.

Genres, Movements & Theory

Headshot

A tightly framed portrait of the head and shoulders, made for professional identification and representation.

Post-Processing & Retouching

Healing Brush

A retouching tool that copies texture from a source area while blending its tone and colour into the destination.

px (brush size)
Files, Metadata & Workflow

HEIF

A modern container format using video-derived compression to store images at roughly half the size of JPEG for equivalent quality.

MB
Composition & Visual Design

High Angle

A viewpoint above the subject, looking downward.

degrees
Sensors & Digital Capture

High ISO Noise Reduction

In-camera processing that smooths noise in high-sensitivity images before writing the JPEG.

levels
Lighting & Flash

High-key Lighting

A lighting approach in which most tones sit in the upper half of the range, with few dark shadows and a bright background.

Motion, Video & Creative Techniques

High-speed Photography

Capturing events too fast for the eye, using very brief flash durations or specialised high-frame-rate cameras.

µs
Lighting & Flash

High-speed Sync

A flash mode that fires a rapid train of pulses during the whole travel of the shutter slit, allowing flash above the normal sync speed.

stops lost
Exposure & Metering

Highlight Alert

A playback warning, often called blinkies, that flashes any area of the image where the brightest tones have clipped.