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A tripod head is the part of a tripod system that attaches the supported device (such as a camera) to the tripod legs, and allows the orientation of the device to be manipulated or locked down. Modular or stand-alone tripod heads can be used on a wide range of tripods, allowing the user to choose which type of head best suits their needs.
The EF 70–300mm f / 4.5–5.6 DO IS USM lens. This lens makes use of Canon's Diffractive optics rather than a traditional lens of wholly refractive design. This allows the lens to be more compact, albeit heavier and much more expensive than a lens of conventional design.
Fixed focus can be a less expensive alternative to autofocus, which requires electronics, moving parts, and power.Since fixed-focus lenses require no input from the operator, they are suitable for use in cameras designed to be inexpensive, or to operate without electrical power as in disposable cameras, or in low-end 35 mm film point and shoot cameras, or in cameras featuring simple operation.
The focus itself may be adjusted in a variety of ways. Larger view cameras and the like slide the lens closer or further from the film plane on rails; on smaller cameras, a focus ring on the lens is often rotated to move the lens elements by means of a helical screw. Other systems include levers on the lens or on the camera body.
The M192 Lightweight Ground Mount is a tripod fielded by the United States armed forces. It was designed and developed by Capco, Incorporated under contract through Picatinny Arsenal to replace the M122 tripod. [1] The United States Army named the tripod one of 2005's top ten inventions. [1] It was designed for use with the M249, M240B, and M240L.
In geometrical optics, a focus, also called an image point, is a point where light rays originating from a point on the object converge. [1] Although the focus is conceptually a point, physically the focus has a spatial extent, called the blur circle. This non-ideal focusing may be caused by aberrations of the imaging optics.
In photography, manual focus override, also known as full-time manual focus, allows manual intervention in the autofocus acquisition process simply by turning the focus ring on a photographic lens. There are a number of technologies used to implement this feature.
These are practical because of autofocus, and because the camera processor can automatically adjust the lens to keep it in focus while changing focal length ("zooming") making it suitable for still photography where a change in magnification of the subject, as demonstrated below is not a problem. The change in the subject size is a significant ...