Perspective control lenses have special tilt and shift movements for correcting converging lines (shift movement) in architectural images, for example, and adjusting the plane of sharp focus (tilt movements) for objects at an angle to the camera. By applying a vertical shift you can bring the top of a tall building into the frame without […]
All lenses produce a circular image on the camera sensor or film, and this ‘image circle’ must be at least large enough to cover the full film/sensor area. Different lenses designed for different sensor sizes and formats have different-sized image circles. Lenses designed for APS-C format cameras, for example, have a smaller image circle than […]
Any program which can edit, enhance or manipulate digital images is technically an image editor, though usually this term is reserved for more advanced, technical programs like Photoshop rather than simpler everyday photo management tools like Apple Photos or Google Photos.
Camera lenses used complex configurations of different optical elements, often cemented or fixed together in ‘groups’. Lens groups may be designed to counteract common optical aberrations and you may have autofocus ‘groups’ and zoom groups. Lens elements and groups often move relative to each other in complex ways as the focus and zoom settings are […]
STM stands for stepper motor lenses, a new type of autofocus motor used by Canon in some of its lenses. Stepper motors offer fast, precise and quiet focus adjustments, so these lenses are well suited both to regular stills photography and to video, where autofocus noise can be picked up very easily by the camera’s […]
The lens is a fundamental part of any camera. It’s what creates the image on the camera sensor (or film). Some cameras have a fixed, non-removable lens while others offer interchangeable lenses. Your choice of lens has a major impact on the appearance of your pictures, including the lens’s focal length (angle of view) and […]
Camera lenses are made up of not just one single lens but many different lens ‘elements’, sometimes cemented or fixed together in ‘groups’. A comparatively simple prime (non zoom) lens may have 6-7 elements while a complex zoom lens might have 17 or more. The different lens elements are needed to compensate for a variety […]
Digital cameras come in a multitude of different types and sizes, and some of the jargon can be quite unhelpful. For example, ‘compact’ cameras aren’t necessarily compact and the real difference is that they have non-removable lenses. DSLRs and CSCs are both examples of interchangeable lens cameras, or ILCs, and these are differentiated by their […]
‘Alpha’ is the generic brand name used by Sony for its interchangeable lens cameras. This can be confusing because Sony makes cameras in two types – SLT (single lens translucent) and mirrorless models. Both are Alphas, but the Alpha A9 (mirrorless) and Alpha A99 II (SLT) are entirely different cameras with different lens mounts and […]
SLT cameras are made by Sony as a kind of hybrid of the regular digital SLR design and the always-on live view of a mirrorless camera. They do have a mirror in the body, but it doesn’t flip up and down when you fire the shutter. Instead, it has a translucent surface so that the […]
The lens mount used by Sony’s Alpha SLT cameras.
This is an attachment for tripod heads designed to make it quicker to remove the camera for handheld photography and re-attach it. You attach the quick release plate to the camera with a slotted screw or butterfly nut, then clip the quick release plate on to the tripod head with a sprung catch or a […]
Gain is a term you’re likely to meet in video rather than stills photography. It basically means turning up the input signal strength to record a decent value. Videographers are more likely to talk about increasing the ISO setting rather than the ‘gain’, though it amounts to the same thing. It’s still used for audio […]
As the name suggests, stepping motors move in small, incremental steps. They are simple, reliable and offer a good deal of control and precision. They’re now being used by Canon (STM lenses) and Nikon (AF-P lenses) in a number of consumer-orientated lenses, where they offer fast, quiet and smooth autofocus.
A mounting system first developed by GoPro but now used widely by other action camera and accessory makers. In theory, any GoPro mount compatible item should be compatible with any other.
Most cameras have a hotshoe for attaching flashguns and other accessories. These are ‘hot’ because they have the electrical contacts needed to connect with and trigger the accessory that’s been added. A cold shoe is simply the same kind of mounting plate but without the connections. For example, they’re used for attaching video lights (which […]
This is a sensor and lens format used by Olympus and Panasonic for their mirrorless camera ranges. The MFT sensor measures 17.3 x 13.0mm, so it’s smaller than the APS-C sensors used in rival mirrorless cameras. This does have a modest effect on overall image quality, but the payback is the both MFT cameras and […]
Aspherical lenses offer better correction for many common lens aberrations than regular spherical lenses. Lenses with a spherical profile are easier to grind into the correct shape, but aspherical lenses have a more complex profile that’s more difficult and more expensive to make. Many modern lenses use moulded aspherical elements instead to get round this. […]
Reproduction ratio is a term used in macro photography to indicate the degree of magnification. A ratio of 1:1 is usually considered the minimum for ‘true’ macro photography. This means that an object is reproduced at exactly the same size on the sensor or film surface as it is in real life. If the first […]
An apochromatic (APO) lens is designed to offer improved correction of chromatic aberration and spherical aberration using specialised materials and combinations of lens elements. It’s a selling point for lenses, though only indicates the lens design used and isn’t really a guarantee of good performance on its own.