A C mount is a type of lens mount commonly found on

16 mm 16 mm film is a historically popular and economical gauge of film. 16 mm refers to the width of the film (about inch); other common film gauges include 8 and 35 mm. It is generally used for non-theatrical (e.g., industrial, edu ...

movie camera A movie camera (also known as a film camera and cine-camera) is a type of photographic camera that rapidly takes a sequence of photographs, either on an image sensor or onto film stock, in order to produce a moving image to project onto a movie sc ...

closed-circuit television camera A closed-circuit television camera can produce images or recordings for surveillance or other private purposes. Cameras can be either video cameras, or digital stills cameras. Walter Bruch was the inventor of the CCTV camera. The main purpose o ...

machine vision Machine vision (MV) is the technology and methods used to provide imaging-based automatic inspection and analysis for such applications as automatic inspection, process control, and robot guidance, usually in industry. Machine vision refers to ...

cameras and

microscope A microscope () is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisi ...

phototubes. C-mount lenses provide a male thread, which mates with a female thread on the camera. The thread is nominally in diameter, with 32 threads per inch (0.794 mm pitch), designated as "1-32 UN 2A" in the

ANSI The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organi ...

B1.1 standard for unified screw threads. The flange focal distance is for a C mount. Merely to say that a lens is "C-mount" says very little about the lens's intended use. C-mount lenses have been made for many different formats. C-mount lenses are built for the 8 mm and 16 mm film formats and the 1/3", 1/2", 2/3", 1", and 4/3" video formats, which corresponds to a range of image circles approximately from 5 to 22 mm in diameter. Depending on the format, the design of the lens and its performance will differ considerably. For example, for the 4/3 format, a 12 mm lens is a wide-angle lens and will have a retrofocus design. For the 2/3-inch format, a 12 mm lens is "normal" and can have a simple and fast double Gauss layout. For the 1/3-inch format, a 12 mm lens is long and can have a telephoto design. Some TV lenses lack provision to focus or vary the aperture, so may not operate properly with film cameras. Also, some TV lenses may have bits that protrude behind the mount far enough to interfere with the shutter or reflex finder mechanisms of a film camera. Although C-mount lenses have a back focal distance far too short to be used with 35 mm film SLRs or any existing digital SLR, they can be mounted on interchangeable-lens mirrorless digital cameras such as the Micro Four Thirds used by Olympus and Panasonic. However, the vast majority of C-mount lenses produce an image circle too small to effectively cover the entire sensor which has approximately 22 mm diagonal, this produces

vignetting In photography and optics, vignetting is a reduction of an image's brightness or saturation toward the periphery compared to the image center. The word '' vignette'', from the same root as ''vine'', originally referred to a decorative bord ...

. The

Nikon 1 series The Nikon 1 series is a discontinued camera line from Nikon, originally announced on 21 September 2011. The cameras utilized Nikon 1-mount lenses, and featured 1" CX format sensors. The series included the Nikon 1 V1, J1, J2, and S1 with a ...

and the

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can use C-mount lenses without vignetting. C mount was created by

Bell & Howell Bell and Howell LLC is a U.S.-based services organization and former manufacturer of cameras, lenses, and motion picture machinery, founded in 1907 by two projectionists, and originally headquartered in Wheeling, Illinois. The company is now ...

for their Filmo 70 cine cameras. The earliest Filmos had slightly different mounts, known as A mount, and B mount. C mount was found on Filmo 70 cameras with serial numbers 54090 and higher, probably from about 1926. Soon after, other camera manufacturers adopted the same mount, and it became a

de facto standard A ''de facto'' standard is a custom or convention that has achieved a dominant position by public acceptance or market forces (for example, by early entrance to the market). is a Latin phrase (literally " in fact"), here meaning "in practice b ...

for 16 mm cine cameras.

CS mount

CS-mount has a flange focal distance of , compared to for a C mount, but is otherwise the same as C-mount, including the fact that lenses for many different formats are made for it. CS-mount lenses are built for the smaller formats, 1/2 inch and down. {, class="wikitable" , + , Combinations: C, CS and extension adapter ! , Camera
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References

ISO ISO is the most common abbreviation for the International Organization for Standardization. ISO or Iso may also refer to: Business and finance * Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007 * Iso ...

10935:1996, "Optics and optical instruments -- Microscopes -- Interfacing connection type C"

External links

Making Digital Camera Microscope Adapters
The section "Understanding C-Mount and CS-Mount Standard Mechanics, Optics, and Cameras" discusses the standards and custom machining of C-mount apparatus.
List of some C-mount lenses
Collection of cine optics and photos of them.

Selection of Lens and extension ring/tube for machine vision
C-Mount explained
Explanation of C-mount and CS-mount Lens mounts Film and video technology

CS mount

See also

References

External links