Glossary
Terms from across the manual, with the abbreviations and alternative names you will find in camera and software menus.
A
- Aperture f-stop
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The ratio of the focal length to the diameter of the entrance pupil. Each full stop (f/2.8 → f/4) halves the amount of light. It also affects depth of field.
- Arc
-
Moving the camera around the subject in a circle; the subject stays in the centre of the frame.
- Aspect ratio
-
The ratio of picture width to height, for example 16:9 (≈1.78:1) or 2.39:1.
B
- Backlight rim light
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Light from behind the subject that outlines its edge and separates the character from the background.
- Bit depth
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The number of levels per channel: 8 bits = 256, 10 bits = 1,024, 12 bits = 4,096. Greater depth reduces the risk of banding when grading.
- Bitrate data rate
-
The amount of data per second, typically in Mb/s. File size = bitrate × duration.
C
- Cardioid
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A heart-shaped microphone polar pattern: sensitive at the front, rejecting sound from the rear.
- CBR / VBR constant / variable bitrate
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A constant bitrate keeps the same number of bits per second; a variable bitrate allocates them according to how demanding the picture is.
- Chroma subsampling
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Notation such as 4:4:4, 4:2:2, 4:2:0: how much colour information is stored compared with luminance. Less colour = a smaller file and a worse key.
- Codec
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An algorithm for compressing and decompressing picture or sound (H.264, ProRes, AV1…).
- Colour rendering indices CRI / TLCI / SSI
-
Metrics that express how faithfully a light source renders colours compared with a reference light. Important with LED sources.
- Colour temperature
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The colour cast of white light, in kelvin. Lower values (~3200 K) are warm, higher ones (~5600 K and above) cooler. It is compensated with the white balance setting.
- Container wrapper
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A file format that wraps video, audio, subtitles and metadata (MP4, MOV, MXF, MKV). A container is not a codec.
- Contrast ratio full on/off
-
The ratio of the illuminance of a full-white and a full-black image. With projectors it depends heavily on the ambient light in the room.
D
- DCP Digital Cinema Package
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A package of files for screening in a digital cinema according to the DCI specification. The picture is encoded in JPEG 2000.
- Deepfake
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Under the EU AI regulation, AI-generated or manipulated image, audio or video content that resembles existing persons, places or events and would falsely appear to be authentic.
- Depth of field
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The range of distances that appears sharp. It gets shallower with a wider aperture (a lower f-number), a longer focal length and a closer focus distance.
- Dolly push-in / pull-out
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Physically moving the camera towards or away from the subject, typically on a dolly. Unlike a zoom, it changes perspective.
- Dynamic range
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The span between the darkest and the brightest tones a camera records with usable detail. It is given in stops (EV).
E
- eARC Enhanced Audio Return Channel
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The HDMI audio return channel from a TV to an amplifier or soundbar, with support for advanced audio formats.
- EDID Extended Display Identification Data
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Data with which a display tells a source which resolutions and formats it supports. A common cause of ‘no picture’ in AV systems.
- Extreme close-up ECU
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A frame showing part of a face or an object, for example the eyes.
- Extreme wide shot EWS
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A landscape or space in which a person is a small element. Often used as an establishing shot.
F
- Fill light
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A weaker source on the opposite side that softens the shadows cast by the key. The key-to-fill ratio sets the contrast of the face.
- Frame interpolation
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Calculating in-between frames to raise the frame rate or create slow motion. The result is an estimate of the motion, not a recorded reality.
- Frame rate fps
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The number of separate images recorded or played back per second. It determines how smooth motion looks and how much time each frame covers.
G
H
- HDMI High-Definition Multimedia Interface
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A digital interface for uncompressed picture, multichannel audio and control data over a single cable.
- HDR high dynamic range
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Video with brighter highlights and a wider range of tones. For television it is defined by ITU-R BT.2100 through the PQ and HLG curves.
- HLG Hybrid Log-Gamma
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A relative HDR curve from ITU-R BT.2100 designed with compatibility with older displays in mind; widespread in broadcasting.
I
- Intra-frame all-intra
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Every frame is compressed on its own. Larger files, but easy decoding and precise editing on any frame.
- ISO exposure index
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On digital cameras, a setting for the gain and mapping of the signal, not a physical ‘sensitivity’ of the sensor. Higher ISO brightens the picture but does not add light.
J
K
- Key light
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The main source, which sets the direction, hardness and character of the light on a character.
L
- Lens shift
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Optically moving the image up, down or sideways without keystone distortion, unlike digital (keystone) correction.
- Letterbox
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Black bars above and below the picture when the picture is wider than the display.
- Light output lumens
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According to ISO/IEC 21118, the average illuminance at 9 points of a full-white image (lux) multiplied by the image area in m².
- Log encoding log recording
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A logarithmic transfer function that squeezes the sensor’s wide dynamic range into the signal. The picture looks flat and needs a transform or grading.
- Loudness range LRA
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The difference between the quieter and louder parts of a programme in LU, according to EBU Tech 3342.
- LUFS / LKFS loudness units relative to full scale
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The unit of integrated loudness according to ITU-R BS.1770. LUFS (EBU) and LKFS (ITU, ATSC) are the same quantity.
- LUT look-up table
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A table that maps each input colour to an output colour. A technical LUT converts between colour spaces; a creative LUT creates a look.
N
- Native ISO base ISO
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The ISO value at which the manufacturer states the best balance of dynamic range and noise. Some cameras have two (dual native ISO).
- ND filter neutral density filter
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A grey filter that cuts light evenly without changing its colour. It lets you keep your chosen shutter speed and aperture even in bright sunshine.
P
- Pan
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Rotating the camera horizontally around a vertical axis; the camera stays in place.
- Pedestal
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Moving the whole camera vertically up or down without tilting.
- Pillarbox
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Black bars to the left and right when the picture is narrower than the display.
- PQ Perceptual Quantizer
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An absolute HDR curve (SMPTE ST 2084, ITU-R BT.2100) that encodes luminance up to 10,000 cd/m².
- Proxy
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A lightweight, lower-quality copy of the footage for smooth editing. At the finishing stage the project is relinked to the original files.
R
- Rec.709 BT.709
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The ITU-R recommendation for HDTV: colour primaries, resolutions and transfer parameters. The standard target for SDR output.
- Rolling shutter
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The sensor reads out its rows one after another rather than all at once. With fast movement, vertical lines lean (the ‘jello’ effect). The opposite is a global shutter.
- Room tone ambience
-
A recording of the ‘silence’ of a location. It is used to fill gaps in dialogue and smooth over cuts.
S
- Shutter angle
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Shutter speed expressed as a share of the frame duration. It comes from the rotating sector shutter of film cameras: time = (angle / 360) × (1 / fps).
- Shutter speed
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How long the sensor is exposed to light for each frame, for example 1/50 s. A longer time = more light and more motion blur.
T
- T-stop
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An f-number corrected for the lens’s actual light transmission. Cine lenses are marked in T-stops so they can be swapped without changing exposure.
- Throw ratio
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Projection distance divided by image width. A ratio of 0.5 means a 2 m wide image is produced from 1 m away.
- Tilt
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Rotating the camera up or down around a horizontal axis; the camera stays in place.
- Timecode
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The address of a frame in the format HH:MM:SS:FF (hours, minutes, seconds, frames). At 29.97 and 59.94 fps, drop-frame timecode is also used, marked with a semicolon.
- Timeline
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The workspace of an editing application: video tracks (V1, V2…) and audio tracks (A1, A2…) arranged in time.
- Truck
-
Moving the camera sideways, parallel to the subject.
- True peak dBTP
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An estimate of the actual peak of the analogue waveform between samples (using oversampling). It protects against distortion during conversion and compression.
U
- Upscaling super-resolution
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Increasing resolution. Classic methods interpolate pixels; machine-learning models estimate detail, which means filling in what was never in the recording.
V
- Vectorscope
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A circular scope that shows hue (angle) and saturation (distance from the centre). It helps you find colour casts and check skin tones.
W
- Waveform monitor
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A scope that shows the luminance (or the RGB channels) of the picture from left to right. The basic tool for checking exposure.
The definitions are general; specific values from standards are given in the articles, with sources. Checked: .