Search results
Results From The WOW.Com Content Network
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 ...
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.
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 ...
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".
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 ...
A body-cap lens is an extreme type of pancake lens that is designed to both protect the camera internals as a body cap normally would, yet still allow the user to take photos. These lenses are manual focus only and generally have no more than a couple of optical lens elements, no image correcting elements, a very-slow fixed aperture, an ...
Although the ME F was an interchangeable lens camera (the photographer could remove and exchange its lens for another), its AF function required the unique SMC Pentax AF 35 mm–70 mm f/2.8 Zoom Lens autofocus lens using a special Pentax K-F lens mount. Unlike all later Pentax AF SLRs, the ME F did not have the focusing drive motor and keying ...
Varifocal lenses are also used in many modern autofocus cameras as the lenses are cheaper and simpler to construct and the autofocus can take care of the re-focussing requirements. Many modern zoom lenses are now confocal, meaning that the focus is maintained throughout the zoom range. Because of the need to operate over a range of focal ...