The lens mount used by Sony’s Alpha SLT cameras. Because these cameras have a mirror in the body, even though it’s a non-moving one, the rear of the lens is further from the sensor, so Alpha mount lenses are physically different to Sony’s E-mount lens range. You can use Alpha lenses on an E-mount camera with a lens adaptor, but not the other way round.
Cameras
8K video
8K video has a horizontal resolution of around 8,000 pixels and is still in its infancy, though Canon, Sony and Nikon now all make 8K Mirrorless Cameras.
6K video
6K video has a horizontal resolution of around 6,000 pixels, or 50% more than 4K video. It’s now starting to appear on some mid-range video cameras, but is used mostly for capturing higher resolution footage for downsampling to 4K (for higher quality) or to allow more leeway for cropping and panning effects in post production.
4K video
4K video is a catch-all term for video with a horizontal resolution of around 4,000 pixels. It can include 4K UHD (3,840 x 2,160 pixels) and Cinema 4K (4,096 x 2,160 pixels).
4K UHD
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 4,096 x 2,160 pixels and the aspect ratio is slightly wider than the 16:9 standard for HD video. In fact, what most makers and users are referring to is UHD video at 3,840 x 2,160 pixels, which does have a true 16:9 aspect ratio.
360 camera
360 cameras create fully immersive video that extends in a full sphere around the camera position, which is usually stationary but could also be mounted on a skydiver’s helmet, for example. There are two ways of working with and watching 360-degree video. One is to use the video as raw material for creating a regular rectangular video, but with the freedom to pan around through a full 360 degrees during the editing process as you choose your viewpoint or create your own ‘panning’ shots. Another is to distribute the 360 video as-is using a suitable display system so that viewers can explore the scene on their own, choosing which direction they want to look in.
35mm camera
35mm film cameras, initially designed for the film industry, remain popular. Full-frame digital cameras with 36 x 24mm sensors are their direct counterparts.
1/2.3 inch sensor
This is the smallest sensor size in widespread use for photography. You’ll find it (or sensors of a similarly small size) in smartphones, point and shoot cameras and some bridge and long zoom travel cameras.
1 inch sensor
A new sensor size roughly half way between the small sensors in point and shoot digital cameras and the much larger ones in digital SLRs and mirrorless cameras. It’s found in more advanced high-end compact cameras, and Nikon uses it for its Nikon 1 mirrorless cameras. It’s been adopted by a number of makers as a way of getting better image quality from compact (non interchangeable lens) cameras.
5-axis stabilization
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 additional movements can pose problems during handheld filming. 5-axis stabilisation used in the Pentax K-1 full frame DSLR, Olympus OM-D mirrorless cameras and the latest Sony A7-series compact system cameras.