Glossary of Terms
AE
Autoexposure
AF
Autofocus
Anti-Distortion Shutter
Designed to minimise the 'rolling shutter' problem found in traditional electronic shutters.
Aperture
The opening in which light can travel through a lens, adjusted by a diaphragm of overlapping blades
Aperture Ring
A ring on the lens which controls the aperture diameter.
APS-C
A sensor with a size of 25.1 x 26.7mm, commonly referred to as a crop sensor.
Back-Illuminated
A reconfiguration of a traditional sensor design to improve low light performance.
Bi-colour
A lighting system where the colour can be adjusted from warm to cool.
Blackout (blackout-free)
The time between taking photos, where an optical viewfinder is covered by the mirror or the electronic viewfinder is covered by the shutter.
Bokeh
The out of focus blur created by a lens.
Camera Shake
When a camera moves while an image is captured due to handheld shooting or unstable equipment, resulting in image blur.
Cardioid
A kind of polar pattern, with highest sensitivity from in front of the microphone, practically no sensitvity from behind, and low sensitivity from the sides.
CCD
Charge-Coupled Device. A type of sensor known for its high image quality.
CCT
Correlated Colour Temperature. A more technical term for colour temperature, although they mean the same thing.
Chromatic Aberration
An undesirable effect caused by the different wavelengths of coloured light focusing in different positions or at different distances. It that appears as coloured fringing and is prevalent in areas with strong contrast and more prominent at the edges of an image.
Circular Polarising
A filter that removes polarised light from non-metallic surfaces. In practical terms this includes reducing reflections off glass or water, reducing haze, increasing the intensity of blue in the sky and improving colours and colours overall.
CMOS
Complementary Metal-Oxide Semiconductor. A type of sensor known for its power efficiency.
Cold shoe
A standardised mount for connecting speedlights that doesn't send electronic signals.
Colour Depth
Refers to the number of colours that a device is capable of representing. A scanner with 48 bit colour depth can record 2^16 colours per red, green and blue channel, or over 281 trillion colours.
Colour Temperature
A measurement unit, expressed in Kelvins (K), that refers to how warm (yellow) or cool (blue) a light is.
Condenser
A microphone thats great for vocals, high frequencies and delicate sounds. They are constructed using a thin diaphragm and solid backing plate.
Constant Maximum Aperture
A zoom lens with a maximum aperture that remains constant throughout the zoom range.
Continuous Shooting
A drive mode where a camera takes multiple photos while the shutter button is held down.
Contrast
The difference between light and dark tones in an image.
Counterbalance
A way of balancing out the weight of a camera and lens so that regardless of the position set the camera remains steady without having to lock the angle in.
CRI
Colour Rendering Index. A measurement that describes how accurate a light source reproduces the colour of an object under it's illumination, compared to it being illuminated by daylight.
D-Max
Relates to the density of the black point on a given media. On a scanner, it denotes the darkest tones at which the unit can still record details. A 4.0 D-Max means a contrast ratio of 10000:1.
DCI (4K)
Digital Cinema Initiatives. A video with a resolution of 4096x2160 pixels, also called Cinema 4K.
Depth of Field
The range of an image, from nearest to farthest, which is acceptably sharp.
Diffuser
Something which diffuses a lightsource by scattering it in different directions. Diffuse light means more even illumination across an area.
DIGIC 6 (Canon)
Canon's proprietary digital camera processor.
Directional
A microphone that picks up sounds from a specific direction.
Distortion
An undesriable warping effect created by lenses. A lens can create barrel distortion, where lines bend outwards, or pincushion distortion, where lines bend inwards.
DNxHD
A high quality, lossy video compression format developed by Avid.
DPI
Dots per inch. The resolution that a device is capable of reproduction over one line. Traditionally refers to the dots of ink in a print, however is often used interchangely with PPI (pixels per inch) for digital images.
dSLR
Digital Single-Lens Reflex. An older style of camera where the image captured on the sensor and seen through the viewfinder comes from the same source (through the lens). The image in the viewfinder is projected from the lens using a mirror and prism mechanism (called an optical viewfinder), with the mirror moving out of the way when the camera records an image.
DX
Nikon's series of crop sensor cameras.
Dynamic Range
The ratio between the darkest and brightest tone that a camera can capture in a single image.
Effective Aperture
The diameter of an aperture when seem through the front of a lens. Also known as the Entrance Pupil.
EXPEED (Nikon)
Nikon's proprietary digital camera processor.
Exposure
The amount of light registered by a camera. Controlled by the aperture, shutter-speed and ISO.
F-Stop
The ratio of a lense's focal-length compared to it's effective aperture's diameter.
Field of view
The maximum angle a camera can capture.
Fisheye
A type of ultra wide lens that distorts a scene to produce a 'bulging' effect, meant to replicate how a fish would see underwater.
Flare
A loss of contrast, or hazy look, created by a bright lightsource.
Flash Coverage
The angle of the flash's beam, how much it spreads or condenses light.
Flash Power
How bright a flash is. The scale used can vary from manufacturer to manufacturer.
Flash recycling
The amount of time it takes a flash to charge between two bursts of light.
Flash Zoom
The feature of a flash to zoom in and out, adjusting the flash coverage, based on a lens focal length.
Fluid Video Head
A kind of tripod head that contains an internal hydraulic system, which provides friction, allowing for smoother movements when shooting video.
Focal Length
Focal length is a number used for lenses to describe their angle of view. A small focal length lens will show a wide angle of view and a large focal length lens will show a narrow angle of view.
Focal Plane
The point at which light rays converge behind a lens to achieve a sharp real image. This is where the sensor sits.
Focal Plane Shutter
A shutter system where a set of two curtains operate in tandem, where the first curtain opens to begin an exposure and the second curtain follows it to end an exposure.
Focus Assist
A feature that zooms in on a portion of the scene so that manual focus can be easier to acheive.
Focus Breathing
A change in focal length as a result of adjusting focus.
Focus Point
The point at which at which a camera's autofocus system establishs focus.
FPS
Frames Per Second. The amount of still images taken over a second, used when defining a camera's shooting or video capabilities.
Fringing
Another word to describe chromatic aberration.
Full Frame
A sensor with a size of 36 x 24mm, the same size as an image captured by 35mm film cameras.
Full Frame Equivalent
A term used desribe a focal length after a camera sensor's crop factor has been accounted for.
Full HD
Full High Definition. A video with a resolution of 1920x1080 pixels.
FX
Nikon's series of full frame cameras.
Ghosting
The appearance of transluscent shapes floating in an image which are created by bright light bouncing off its internal glass elements. Often used for intentially, or added in post production, to create a certain look.
Guide Number
A number used to indicate flash power, defining the distance at which optimal exposure will be acheived with the flash at full power. The formula is Guide Number = Subject Distance From Flash × f-stop
GN
An abbreviation for Guide Number.
Hard light
HD
High Definition. A video with a resolution of 1280x720 pixels.
HDR
High Dynamic Range. A mode which expands the dynamic range possible to capture in one image, usually by taking multiple photos at different exposures and blending them together.
HLG
Hybrid Log Gamma. A way of coding HDR and SDR footage into the same broadcast signal.
Hot shoe
A standardised mount for connecting speedlights that can also send electronic signals.
HSS
High Speed Sync. A function that allows a camera to use faster shutter speed than the standard flash sync speed. The trade off to this is a higher shutter speed means lower flash power.
IBIS
In-Body Image Stablisation. A stabilisation method in which the cameras sensor moves around to offset camera shake.
Image Stabilisation
A technology that attemps to offset movements caused by camera shake for sharper photos at slower shutter speeds.
Interchangeable Lens
A camera system where the lenses can be removed and swapped around.
Interval Timer
A setting where the camera will automatically capture images at defined intervals for a set period of time.
Iris
Another word for aperture.
ISO
A number referring to the amount of gain applied to the light data captured by a camera's sensor. Colloquial known as the sensitivity of the sensor.
kHz
Kilohertz. Used to measure audio sample rate, which determines the range of frequencies, from low to high, that are measured by second.
Live View
A mode on dSLR cameras where the mirror is raised so that the sensor can capture, and project, a real time image of the scene on it's rear screen.
Log
A picture profile which redistributes tonal data as a logarithmic, rather than linear, curve. Log footage comes out flat, but has more verstatiliy to colour grade.
Low-Pass Filter
A filter that stops high frequency image information from reaching the sensor, reducing the effects of moire but creating a slight blur. Also known as an anti-aliasing filter.
Lumen
The amount of light a unit emits.
LUT
Look-Up Table. A preset that alters raw footage to produce a specific looking edit.
Lux
The amount of light that falls on a surface.
Macro
A lens designed for close up photography.
Magnification (macro)
The relationship between the size of a subject in real life and its size on the projected image. A 1:1, or 1.0x magnification will mean that when in focus, a subject is the same size in the projected image as it is in real life.
Maximum Aperture
The widest a lenses aperture can open. This is useful for establishing the low light and bokeh performance of a lens.
Medium Format
A sensor with a size greater than 44x33mm, but smaller than large format.
Megapixel
A unit of resolution equal to 1,048,576 pixels.
Micro Four Thirds
A sensor with a size of 17.3 x 13mm.
Minimum Focusing Distance
The minimum distance a lens can achieve focus on a subject.
Mirrorless
A type of modern camera that doesn't have a mirror in front of the sensor, like those in dSLR's. Instead of an optical viewfinder, an electronic viewfinder is used, which takes a video feed from the camera's sensor.
Modelling Light
A low power light, used to provide a 'preview' of how the flash light will shape a subject.
Moiré
An effect caused by a repetitive pattern in a scene that exceeds the resolution (or pattern of pixels) of a camera's sensor.
Mono
A microphone with one capsulre to record one track of audio. Typically found in directional microphones.
Monoblock
A light unit that contains both a power supply and lamp.
Native ISO
A sensors natural sensitivity, without altering the signal registered by adding or reducing gain. Moving away from the Native ISO can reduce dynamic range and introduce noise.
Neutral Density Filter
Neutral Density Filter. A filter that reduces the amount of light coming through a lens without altering the colour. The ND number refers to the fraction of light that is allowed through, for example, a ND400 lets through 1/400th of the original light. Useful in video for maintaining specific shutter speed to frame rate ratios, or in photography to achieve longer exposures or wider apertures.
NFC
Near-Field Communication. A technology that allows two devices to communicate with each other.
NIT
A unit of measurement to describe how bright a screen is. The higher the number, the brighter the screen.
Noise
An often undesirable effect where interference in the light values registered by an cameras sensor cause their colour and tone to deviate from their actual values, creating a speckled or grainy look over the image.
Omni Directional
A kind of polar pattern, that picks up sound from all directions.
Open Up
To increase the size of the aperture, or decrease the f-stop.
Optical Image stabilisation
A type of image stablisation that is built into the lense.
Optical Zoom
Zoom that is created by moving optical elements within a lens.
Perspective
The way a three dimension space, and the relationship between the elements within that space, is transposed into the two dimensions of the photograph.
Phase-detection
An autofocus system know for its speed. It works by spliting light entering a lens into two images, and using a mirror, compares them on a seperate sensor by making adjustments until they converge.
Pixel
The smallest unit by which a digital image can be captured and displayed.
Plane of focus
The plane in front of the camera, parrallel to the sensor, where the scene is theorectically at its sharpest amount of focus.
Polar Pattern
How a microphone picks up sound from the environment around it.
PQ
Perceptual Quantizer. A transfer function that allows for HDR display by replacing the gamma curve used in SDR.
Preamp
A device that adds gain (increases volume) to a mic signal before it is recorded.
Prime
A lens that has a fixed focal length. E.g. 50mm f/1.8 Lens.
ProRes
A high quality, lossy video compression format developed by Apple.
Raw
An image format where information is stored as raw data, rather than undergoing compression and converstion to a different file type.
Rec. 709
The standard colour space for video displays.
Resolution (camera)
The amount of detail that can be recorded, usually expressed by a number of pixels.
Resolution (lens)
The amount of detail a lens can reproduction, which may be greater or lesser than the resolution capaible of being captured by a camera.
SDR
Standard Dynamic Range.
Sharpness
Describes how clear, or crisp, details are within an image.
Shotgun
A design type that improves the performace of a cardoid microphone so that they are even more directional.
Shutter Speed
The length of time that light illuminates a camera's sensor, normally controlled by a set of curtains called a focal plane shutter.
Silent Shooting
A mode that takes a photo by turning a cameras sensor on and off to capture an exposure. Also know as an electronic shutter.
Soft Light
A lightsource which creates undefined, blurry shadows. The transition from shadow to light is gradual. Typically hides texture and reduces saturation of colour.
Standard
A focal length of 50mm, which is said to closest represent the field of view of the human eye.
Stereo
A microphone with two capsules to record two tracks of audio. They create a more immersive, three dimensional sound.
Stop
"A term used to describe changes in light (either brighter or darker). A one stop change is twice, or half, as bright as before. For further stops, the relationship is exponential, calculated by 2^Stops.
Stopped Down
To decrease the size of the aperture, or increase the f-stop.
Super 35
A sensor with an approximate size of 24x14mm, although this varies between manufacturers.
Super-Cardoid
Like a cardoid microphone, but with less sensitivity to the sides and more from behind.
Sync Speed (X-Sync)
The fastest shutter speed that can be used for normal flash photography. It refers to the shortest length of time in which the set of curtains in a focal plane shutter are fully open.
T-Stop
A number that expands on f-stops by accounting for the light lost during transmission through the lens. The number enables more accurate calculations of exposure.
Telephoto
A lens design with a narrow field of view. Colloquially known as a high/long zoom factor.
Tilt Shift
A unique lens which can be tilted, to alter the plane of focus so that it is no longer parallel with the camera sensor, or shifted, to move around the projected image circle.
Time Lapse
A video created from a series of still images taken at regular intervals.
Tracking
When a cameras active autofocus points change automatically to follow the movement of a subject. Commonly used to track eyes, faces or even inanimate objects.
TTL
Through The Lens. An automatic system to determine flash power for a correct exposure. Works by firing a 'pre-flash', and then evaluating it's exposure through the lens, before the real flash is fired.
UHD (4K)
Ultra High Definition. A video with a resolution of 3840 x 2160 pixels
Ultra-wide
A lens with a focal length less than 24mm.
V-Gamut
A wide colour gamut useful for heavy colour grading and high colour reproduction. It is significantly larger than P3DCI and Rec. 709
V-Log
A Panasonic photostyle that reduces contrast and colour saturation so that it can be better altered in post production.
VR
Vibration Reduction. Nikon's image stabilisation technology.
White Balance
A setting that adjusts the colour temperature of an image from warm (yellow) to cool (blue). It is normally designed to neutralise the colour of a lightsource so that it appears white in an image.
Wide-angle
A lens with a focal length between 24mm and 50mm.
X-Processor
Fujifilm's proprietary digital camera processor.
X-Trans
A proprietary Fujifilm sensor type, where the RGB filters in a conventional Bayer array are replaced by an X-Trans filter array.
Zoom
A lens that has a range of focal lengths. E.g. 24-70mm f/2.8 Lens.