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The first mass-produced autofocus camera was the Konica C35 AF, a simple point and shoot model released in 1977. The Polaroid SX-70 Sonar OneStep was the first autofocus single-lens reflex camera, released in 1978. The Pentax ME-F, which used focus sensors in the camera body coupled with a motorized lens, became the first autofocus 35 mm SLR in ...
Shape from focus or shape from defocus is a method of 3D reconstruction which consists of the use of information about the focus of an optical system to provide a means of measurement for 3D information. [1] One of the simplest forms of this method can be found in most autofocus cameras today.
Depth of focus is a lens optics concept that measures the tolerance of placement of the image plane (the film plane in a camera) in relation to the lens. In a camera, depth of focus indicates the tolerance of the film's displacement within the camera and is therefore sometimes referred to as "lens-to-film tolerance".
Mirrorless interchangeable-lens camera. Similar to a digital single-lens reflex camera, but having an electronic or rangefinder type of viewfinder in place of the mirror and pentaprism, to allow a more compact design. See also EVIL camera. MTF: Modulation transfer function. A technical measure of the ability of a lens to create a finely ...
In most digital cameras, by default autofocus is only activated (AF-on) when the shutter button is pressed halfway down, which helps to preserve battery life. However, some photographers find that having AF-on and the shutter release on the same button makes it harder to establish the correct focus point, or hold it once the desired point is ...
Attaining maximum lens speed requires engineering tradeoffs, and as such, "prime" (fixed focal length) lenses are generally faster than zoom lenses. [2] With 35mm film cameras and full-frame digital cameras, the fastest lenses are typically in the "normal lens" range near 50mm; here, there are several relatively inexpensive high-quality fast ...
The lensmeter is also used to check the accuracy of progressive lenses, and is often capable of marking the lens center and various other measurements critical to proper performance of the lens. It may also be used prior to an eye examination to obtain the last prescription the patient was given, in order to expedite the subsequent examination.
When a compatible lens is used with a 1.4× or 2× extender, it will cost the lens a one or two stop decline in aperture size, respectively. Autofocus speed of any used EF lens is also affected. When used with the 1.4× extender, autofocus speed is reduced by 50%. When used with the 2× extender, autofocus speed is reduced by 75%.