Action cam

A small, simple and largely automated video camera (you can also shoot stills) designed to attach to a helmet, handlebars, surfboard or any other kind of object and provide dramatic first-person video of adventure sports and other activities. Almost all use fixed...

ACROS (Fujifilm)

Black and white film simulation mode added to newer Fujifilm cameras. It’s designed to give richer, more intense tonal rendition than the regular monochrome film simulation.

AA batteries

These are used rarely in digital cameras (except in some cheap point and shoot models) but used extensively in external flashguns and battery grips. Alkaline AAs will do in an emergency, but rechargeable NiMH batteries are more cost effective and last longer between...

5-axis stabilisation

The latest kind of image stabilisation technology, where the camera’s sensor can be tilted or shifted on 5 axes to counter a much wider range and types of movement than regular lens-based image stabilisers, and it’s a particular advantage for video, where these...

4K video

The latest consumer video standard, with a horizontal resolution of 4,000 pixels or thereabouts. 4K video is appearing on an increasing number of cameras and even smartphones, and 4K TVs are gaining in popularity. Strictly speaking, the dimensions for 4K video are...

1.5-inch sensor

A unique sensor size used by Canon in its top PowerShot compact camera, the G1 X II. It’s just a little smaller than the APS-C format used by most DSLRs and larger than the 1-inch sensors used in other high-end PowerShot models, so it gets close to the quality...