Lens mount

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Female lens mount of an Minolta XD-7 with male mount of Minolta MC-Rokkor 58mm 1:1.4 lens
Pentax K-7 with visible lens mount

A lens mount is an interface — mechanical and often also electrical — between a photographic camera body and a lens. It is confined to cameras where the body allows interchangeable lenses, most usually the rangefinder camera, single lens reflex type or any movie camera of 16 mm or higher gauge. Lens mounts are also used to connect optical components in instrumentation that may not involve a camera, such as the modular components used in optical laboratory prototyping which join via C-mount or T-mount elements.

A lens mount may be a screw-threaded type, a bayonet-type, or a breech-lock (friction lock) type. Modern still camera lens mounts are of the bayonet type, because the bayonet mechanism precisely aligns mechanical and electrical features between lens and body. Screw-threaded mounts are fragile and do not align the lens in a reliable rotational position, yet types such as the C-mount interface are still widely in use for other applications like video cameras and optical instrumentation.

Bayonet mounts generally have a number of tabs (often three) around the base of the lens, which fit into appropriately sized recesses in the lens mounting plate on the front of the camera. The tabs are often "keyed" in some way to ensure that the lens is only inserted in one orientation, often by making one tab a different size. Once inserted the lens is fastened by turning it a small amount. It is then locked in place by a spring-loaded pin, which can be operated to remove the lens.

Lens mounts of competing manufacturers (Nikon, Canon, Contax/Yashica, Pentax, etc.) are almost always incompatible. In addition to the mechanical and electrical interface variations, the flange focal distance from the lens mount to the film or sensor can also be different. Many allege that these incompatibilities are due to the desire of manufacturers to "lock in" consumers to their brand.

In movie cameras, the two most popular mounts in current usage on professional digital cinematography cameras are Arri's PL-mount and Panavision's PV-mount. The PL-Mount is used both on Arri and R.E.D. digital cinematography cameras, which are in 2012 the most used cameras for films shot in digital. The Panavision mounts are exclusively used with Panavision lenses, and thus are only available on Panaflex cameras or third-party cameras "Panavised" by a Panavision rental house, whereas the PL-mount style is favored with most other cameras and cine lens manufacturers. Both of these mounts are held in place with locating pins and friction locking rings. Other mounts which are now largely historical or a minority in relation to current practices are listed below.

List of lens mount types[edit]

These types are organized by category; find details in the section that follows.

Cinematography
Universal (stills and movie)
Medical
Industrial
CCTV
Scientific

List of lens mounts[edit]

This list of lens mounts is ordered by flange focal distance, from shortest to longest. It includes both digital, still photography and movie lens mounts.

OEM model line(s) Interchangeable type name Frame size Camera type Throat or thread diameter Mount thread pitch Mount type Flange focal distance
Edmund Optics μ-Video S-mount 1/6 inch to 1 inch Security IP Cameras, Automotive Backup cameras, Webcams, Digital Image scanners 12mm 0.5 mm pitch Screw No Flange. Back focal distance from <1mm to 12mm.
Pentax Q Pentax Q 1/2.3 or 1/1.7 inch digital still     Bayonet 9.2 mm
  D-mount 8 mm movie, CCTV 15.88 mm (0.625 inch) 32 TPI Screw 12.29 mm
  CS-mount 1/3 inch, 1/2 inch movie, CCTV, industrial, scientific 25.40 mm (1 inch) 32 TPI Screw 12.52 mm
  C-mount 1/2 inch, 16 mm, 2/3 inch, 1 inch movie, CCTV, industrial, scientific 25.40 mm (1 inch) 32 TPI Screw 17.526 mm (0.69 inches)
Nikon 1 series Nikon 1 mount 13.2 x 8.8mm digital still     Bayonet 17 mm
Fujifilm X-series Fujifilm X-mount APS-C digital still     Bayonet 17.7 mm
Canon EOS M Canon EF-M mount APS-C digital still, movie 58 mm (Outer)   Bayonet 18 mm
Sony Alpha NEX Sony E-mount 35 mm and 23.4 mm × 15.6 mm APS-C digital still, movie 46.1 mm (1.815 inch)   Bayonet 18 mm
Olympus Pen & OM-D series; Panasonic G, GF, GX & GH Series, Blackmagic Design Pocket Cinema Camera, Blackmagic Design Cinema Camera Micro Four Thirds 17.3 mm × 12.98 mm digital still, camcorder ~38 mmA[›]   Bayonet 19.25 mm
Canon EX     camcorder     Bayonet 20 mm
Bolex C-mount 16 mm movie     Breech lock 23.22 mm
Samsung NX NX-mount 23.4 mm × 15.6 mm APS-C digital still 42 mm   Bayonet 25.5 mm
Pentax Auto 110   110 film still     Bayonet 27 mm
Minolta/Leica M bayonet M-mount (aka EM, VM, ZM) 35 mm still 44 mm   Bayonet 27.80 mm
Leitz/Minolta CL, Minolta CLE compact M-mount 35 mm still 44 mm   Bayonet 27.80 mm
Konica Hexar RF KM-mount 35 mm still 44 mm   Bayonet 28 mm (27.80 mm?)
Canon screw mount   35 mm still M39 1 mm Screw
Leica M39 screw mount M39 (aka L-Mount, LSM) 35 mm still, enlargers M39 26 TPI Screw 28.80 mm
Narciss   16 mm still M24 1 mm Screw 28.8 mm
Olympus Pen-F   35 mm half-frame still     Bayonet 28.95 mm
Contax/ (Kiev rf) I, II, III, IIa, IIIa   35 mm still   Double bayonet 34.85 mm
Contax G   35 mm still     Breech lock 29.00 mm
Hasselblad Xpan   35 mm panoramic still     Bayonet 34.27 mm
Nikon Rangefinder Nikon S-mount 35 mm still     Bayonet 34.85 mm
Alpa   35 mm still     Bayonet 37.80 mm
Minolta Vectis V-mount 30.2 mm × 16.7 mm APS still     Bayonet 36.00 mm (38 mm?)
Olympus E, Panasonic Lumix DMC-L, Leica Digilux Four Thirds 17.3 mm × 12.98 mm digital still ~44 mmA[›]   Bayonet 38.67 mm
Aaton universal   16 mm movie     Breech lock 40 mm
Konica F Konica F-mount 35 mm still 40 mm   Bayonet 40.50 mm
Konica A/R AR-mount 35 mm still 47 mm   Bayonet 40.50 mm (40.7 mm)
Miranda Camera Company Miranda bayonet/M44 35 mm and APS-C still, industrial     Bayonet 41.5 mm
Canon R   35 mm still     Breech lock 42 mm
Canon FL   35 mm still     Breech lock 42 mm
Canon FD FD-mount 35 mm still     Breech lock 42.00 mm
Fujica-X Fujica X-mount 35 mm still 49 mm   Bayonet 43.5 mm
Minolta SR/MC/MD SR-mount 35 mm still, medical 44.97 mm   Bayonet (54°) 43.50 mm
Petriflex   35 mm still     Breech lock 43.5 mm
Mamiya/Sekor E   35 mm still     Bayonet 43.5 mm
Canon EOS EF mount (aka ZE) 35 mm still, movie 54 mm[2]   Bayonet 44.00 mm
Canon EOS EF-S mount APS-C digital still 54 mm   Bayonet 44.00 mm
Sigma SA   35 mm still     Bayonet 44.00 mm
Paxette   35 mm still M39 1 mm Screw 44 mm
Praktica B   35 mm still     Bayonet 44.40 mm
(Konica) Minolta AF/Alpha/Dynax/Maxxum, Sony Alpha DSLR/SLT A-mount (aka ZA) 35 mm and APS-C still, industrial 49.7 mm (1.939 inch)   Bayonet (54°) 44.50 mm
Rolleiflex SL35   35 mm still 46 mm   Bayonet 44.46 mm
Exakta, Topcon   35 mm still     Bayonet 44.7 mm
Zenit 39mm Zenit M39 35 mm still M39 1 mm Screw 45.2 mm
Pentax K K-mount (aka ZK) 35 mm still     Bayonet 45.46 mm
Asahiflex   35 mm still 37 mm 1 mm Screw 45.46 mm
Praktica M42 lens mount 35 mm still 42 mm 1 mm Screw 45.46 mm
Yashica/Contax Y/C-mount 35 mm still     Bayonet 45.5 mm
Mamiya ZE   35 mm still     Bayonet 45.5 mm
Kyocera Yashica 230 AF etc. MA-mount 35 mm still     Bayonet ~45.8 mm
Olympus OM OM-mount 35 mm still 46 mm   Bayonet 46 mm
Nikon F-mount Nikon F-mount 35 mm still, industrial 44 mm   Bayonet 46.5 mm
Leica R R-mount 35 mm still     Bayonet 47.00 mm
Contax-N   35 mm still     Bayonet 48 mm
Praktina   35 mm still     Breech lock 50 mm
Tamron T-Thread (Very earliest type) 35 mm still M37 0.75mm Screw 50.7 mm
Tamron Adapt-A-Matic 35 mm still     Bayonet 50.7 mm
Tamron Adaptall 1 & 2 35 mm still     Bayonet 50.7 mm
Arri standard   35 mm and 16 mm movie     Tab lock 52 mm
Arri bayonet   35 mm and 16 mm movie     Bayonet 52 mm
Arri PL   35 mm and 16 mm movie     Breech lock 52 mm
Tamron T2, T-mount or T-thread 35 mm still, industrial 42 mm 0.75 mm Screw 55 mm
Sigma Corporation YS Auto T-Thread 35 mm still 42 mm 0.75 mm Screw 55 mm
Tokina T-thread type 35 mm still 47 mm 0.75 mm Screw 55 mm
Sony Mavica Mavica   digital still     Bayonet 57 mm
Panavision PV mount   35 mm movie     Breech lock 57.15 mm
Mamiya 7/7II   6×7 still     Bayonet 60 mm (approx.)
Mitchell BNCR mount   35 mm movie     Breech lock 61.468 mm
Mamiya 645   6×4.5 still     Bayonet 63.3 mm
Zeiss Panflex 5522/23 for Contax rf   35 mm still   Double bayonet 64.50 mm
Leitz Visoflex II/III   35 mm still     Bayonet (Leica M) 68.8 mm
Pentax 645   6×4.5 still     Bayonet 70.87 mm
Arri Maxi PL   70 mm movie 64 mm     73.5 mm
Pentacon Six   6×6 still     Breech lock 74.1 mm
Hasselblad   6×6 still     Bayonet 74.9 mm
Kowa Six/Super 66   6×6 still     breech lock 79 mm
Pentax 6x7   6×7 still     Bayonet 84.95 mm
Leitz Visoflex I   35 mm still M39 26 TPI Screw 91.3 mm
Bronica S2A   6×6 still 57 mm 1 Bayonet 101.7 mm
Rolleiflex SL66   6×6 still     Bayonet 102.8 mm
Mamiya RZ67   6×7 still     Bayonet 105 mm
Mamiya RB67   6×7 still     Bayonet 112 mm
Canon RC-701 Canon SV   digital still     Bayonet 2/3 inch[3]

Legend[edit]

Legend
Column Description
OEM model line(s) primary manufacturer(s) or model line(s) with this mount
Interchangeable type name interchangeable mounts used by multiple camera body and lens manufacturers
Frame size maximum or typical film format or image sensor size used for this mount
Camera type still, digital still, movie, cinema, CCTV, ...
Throat or thread diameter Nominal inside-female or outside-male major diameter (D) with units: inch, mm, or M (ISO 68-1 metric thread pitch mm)
Mount thread pitch (P) either: (Unified-thread) pitch count/inch, or (metric) mm/thread pitch
Mount type Bayonet, Breech, Screw, ...
Flange focal distance Nominal (mm) distance from film or image sensor to lens mount

Focusing lens mount[edit]

The axial adjustment range for focusing Ultra wide angle lenses and some Wide-angle lenses in large format cameras is usually very small.

So some manufacturers (e.g. Linhof) offered special focusing lens mounts, so-called wide-angle focusing accessories for their cameras. With such a device, the lens could be focused precisely without moving the entire front standard.

Secondary lens mount[edit]

Secondary lens refers to a multi-element lens mounted either in front of a camera's primary lens, or in between the camera body and the primary lens.

(D)SLR camera & interchangeable-lens manufacturers offer lens accessories like extension tubes and secondary lenses like teleconverters, which mount in between the camera body and the primary lens, both using and providing a primary lens mount. Various lensmakers also offer optical accessories that mount in front of the lens; these may include wide-angle, telephoto, fisheye, and close-up or macro adapters.

Canon PowerShot A and Canon PowerShot G cameras have a built-in or non-interchangeable primary (zoom) lens, and Canon has "conversion tube" accessories available for some Canon PowerShot camera models which provide either a 52mm or 58mm "accessory/filter" screw thread. Canon's close-up, wide- (WC-DC), and tele-conversion (TC-DC) lenses have 2, 3, and 4-element lenses respectively, so they are multi-element lenses and not diopter "filters".

Notes[edit]

^ A: The authoritative normative source for 4/3 standards information is Four-Thirds.Org and not 3rd-party reviews.

4/3's published facts:

  • "Size of the 4/3-type Sensor: The standard diagonal length of the sensor is 21.63 millimetres (0.852 in). It is half that of 35-mm film format (36 millimetres (1.4 in) x 24 millimetres (0.94 in) = 43.27 millimetres (1.704 in)) The image circle of the interchangeable lens is specified based on this diagonal length. The focal length is about a half that of a 135 film camera lens assuming the same angle of view."[4]
  • "The foundation for the high picture quality of the Four Thirds system is the lens mount, which is about twice the diameter of the image circle."[5]
  • "Differences between Four Thirds System mount and Micro Four Thirds System mount: Mount diameter reduction; As a result of research aimed at facilitating the design of compact, lightweight lenses while maintaining the current strength, the outer diameter of the lens mount has been reduced by approx. 6 millimetres (0.24 in). ... the Micro Four Thirds System ... specifies the optimum flange back length required to reduce camera size and thickness, assuming the omission of the mirror box. The flange back length has been reduced to about 1/2 that of the Four Thirds System."[6]

So:

  • 21.63mm * 2 = 43.26 millimetres (1.703 in) or ~44mm
  • 43.26mm - 6mm = 37.26 millimetres (1.467 in) or ~38mm
  • (21.63mm)^2 = ( ( 17.3mm ^ 2 ) + ( 12.98mm ^ 2 ) ); See: Pythagorean theorem (5^2 = 4^2 + 3^2)

NOTE: Some published reviews of 4/3 instead cite the (female) "outside diameter" of the lens or mount as ~50mm (and micro-4/3 as ~44mm),[7] and not the appropriate major diameter (D) ~44mm which is the camera body's female mount inside-diameter and the lens's male mount outside-diameter (micro-4/3 ~38mm).

See also[edit]

References[edit]

General references[edit]

External links[edit]