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Action camera jargon buster

By Ryan Shaw

Don't get flustered when buying a new action camera; our simple guide can help you decode the camera jargon.

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Aperture is the hole in the lens through which light passes to hit the image sensor.

Aperture priority

A digital camera setting that allows the user to set the size of the aperture (also called f-stop) and allow the camera to determine the shutter speed for a correctly exposed image.

Auto focus

Abbreviated as AF, auto focus is a function of a digital camera in which the camera automatically focuses on the subject in the centre of the LCD screen or viewfinder.



Most digital cameras have built-in rechargeable lithium ion batteries and come with a charger. These are a clear money-saving upgrade from having to rely on AA batteries, and they last for a good while too. We had to drop our testing of camera battery life a few years ago, simply because models would take too long to run out of charge.

Bridge camera

A bridge camera is one that attempts to "bridge" the gap between digital compact cameras and digital SLRs. They tend to feature a large zoom lens (not interchangeable) and a larger image sensor than a compact.

Burst mode

Burst mode is another term for continuous shooting mode, used by some camera manufacturers.



Stands for Charge Coupled Device. CCDs are sensors in digital cameras to record still and moving images. The light is captured  and converted into digital data, and then recorded by the camera. 

Colour reproduction

Colour reproduction is the ability of a digital camera to record colours that are true to life.

Compact camera

Typically, this is a small digital camera that lacks an interchangeable lens and an optical viewfinder. Photos are composed via the LCD screen at the rear of the camera.

Compact system cameras

Like DSLRs, compact system cameras (also known as CSCs) can use different lenses and generally have larger sensors than compact or bridge cameras. They take great photos but are lighter, slimmer and easier to use than DSLRs.


Composition describes the arrangement of everything included in the final photo.


Digital SLR (DSLR)

A DSLR, or digital single lens reflex camera, is a high-end type of interchangeable-lens camera used by photography enthusiasts and professionals.

Digital zoom

A digital zoom has no moving parts, and the image is cropped and digitally enlarged, reducing the overall quality. Mobile phones with a built-in camera typically feature a digital zoom.


Distortion sometimes occurs when you've zoomed right in or right out. Straight lines near the edge of the image might look slightly bent.



An electronic viewfinder (EVF) is essentially a tiny LCD screen. You use it just like an optical viewfinder, and on most cameras that feature an EVF, you can easily switch the view between the viewfinder and the large LCD screen on the back of the camera. Typically common in compact, bridge and compact system (mirrorless) cameras.


The exposure is the amount of light allowed to fall on to the image sensor in a digital camera, which is determined by the length of time the shutter is open and how wide the lens is allowed to open (aperture).


Face detection

This feature is based on built-in camera software that detects the shape of a human face and automatically sets the focus and exposure for perfect portraits.

Focal length

The focal length of a lens refers to the distance at which objects appear from the camera in a photo, essentially equivalent to the zoom level. Focal length is generally expressed in millimetres, with a small focal length (below 50mm) being classed as wide angle, with larger values (over 50mm) being classed as telephoto.

Frame rates

Frame rates are noted in frames per second (fps). A frame rate is the maximum number of images a camera can shoot continuously in one second. This is important for high-speed action shots and shooting video.



GPS, which stands for Global Positioning System, is a radio navigation system that allows any user on land , sea, or airborne, to determine their exact location, velocity and time, anywhere in the world. Some cameras feature built-in GPS, which is useful for tagging your video/photos with accurate location data. This means, you can track your adventures on a map or you can enter caption information in the metadata — you'll know exactly where a photo or video was taken.



HDR stands for High Dynamic Range, and this an older photography technique recently made popular again with phone cameras. It's a method that adds more 'dynamic range' to a photo, which means, the ratio of light and dark in a photograph. So instead of taking just one photo, HDR uses three photos taken at different exposures. You can use imaging software to combine these three shots to create your perfect photo or in the case of a phone camera, the phone does all the hard work for you.


A graphic representation of the range of tones from dark to light in a photo. Some digital cameras include a histogram feature that enables a precise check on the exposure of the photo.


Image sensor

A sensor within the camera that translates the light coming through the lens into a digital photo.

Image stabilisation

Although the digital camera might be perfectly focused, your photos could still be blurry, especially in dim conditions or if you've zoomed in a lot. This is the curse of camera shake – sometimes even the smallest hand movements affect the picture. Most digital cameras now have effective optical image stabilisation technology, which typically involves the lens or digital sensor moving ever so slightly to compensate for hand movements.


The ISO setting on a digital camera tells you how sensitive the camera's sensor is to light. Using a higher ISO setting (such as 400, 800 or 1600) means it can be easier to take good photos in dim conditions without flash. Although having a high maximum ISO setting on your digital camera is a benefit, using a higher ISO setting can introduce more noise into your pictures, ie the random speckles of colour that can detract from picture quality.


LCD screen

A Liquid Crystal Display (LCD) screen allows you to frame and review your images in addition to displaying camera functions and menus.


Macro mode

A setting on a digital camera that enables users to focus on subjects close to the camera lens.


A megapixel (Mp) equals one million pixels. The term is used in reference to the resolution of the digital camera. More megapixels mean more detail, so you can create bigger prints without noticing blockiness on the picture. Megapixels aren't the be-all and end-all though – the digital camera's lens quality, sensor quality and sensor size play a big role in how sharp and colour-accurate your pictures are.

Memory card

A memory card is what your camera uses to store your photos. There are various types of cards available, with the most common being SD, SDHC, SDXC. If you’re looking to record HD video with your camera, capacity and speed of the card must also be considered.


The camera assesses the amount of light available for a photograph and then adjusts the exposure accordingly. Sometimes, the camera may not be smart enough to accurately judge the amount of light, so the photographer can make manual adjustments. There are three main metering modes available; evaluative metering, spot metering and center-weighted metering.



NFC stands for Near Field Communication, a type of short-range wireless connectivity to enable communication between devices, such as a mobile phone, laptop or digital camera.


Noise refers to the random speckles seen in images. It occurs particularly when photographing areas of even colour, such as the sky. When a higher sensitivity (eg ISO 800 and above) is used, noise becomes more prominent.


Optical zoom

This physically moves the lens within the camera, maintaining image sharpness and resolution.


An optical viewfinder (OVF) uses a mirror and a prism to bounce light through the lens and towards your eye. This means you can see almost exactly what the lens sees, without any delay.


Photo Resolution

Measured in megapixels (Mp), and also relates to the size of the photo.



This is a type of file format that DSLR cameras and some high-end standard cameras can create. It gives maximum image quality and versatility when editing with photo editing software, but file sizes are very large and they require some processing in photo editing software before they can be used.

Red-eye reduction

Some portraits taken with a flash can result in an unsightly ‘red eye’ effect. The built-in technology reduces the chance of red eye appearing in portraits.


Shutter priority

This refers to a digital camera setting or mode that allows the user to set the shutter speed and allows the camera determine the aperture size (also called f-stop) for a correctly exposed image.

Shutter speed

The shutter speed is the unit of measurement which determines how long the shutter remains open as the picture is taken.



A viewfinder is the eyepiece that you look through to frame and focus your subject matter before taking the picture. There are two different types of viewfinder; optical viewfinder (OVF) and electronic viewfinder (EFV). Found on DSLR cameras, an optical viewfinder allows you to see exactly what the lens sees, by looking through the lens using a system of mirrors and prisms. An electronic viewfinder uses a tiny electronic display, very similar to a larger LCD screen.

Video resolution

Determines the sharpness and crispness of the footage. Video resolution refers to the number of pixels in each frame.


White balance

All digital cameras have automatic white balance. This feature goes some way to ensuring your photos' colours are as accurate as possible. Often though, you do get slight colour casts – this is most often seen when you take a photo indoors under a normal household lightbulb and your photo takes on a yellow tint. Thankfully, nearly all digital cameras have manually selectable white balance settings (indoor, daylight, cloudy) to help you achieve accurate colours under different light conditions.


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