Lens Mount Identification
Argus
The Argus 21 50mm f3.5 Cintar can be removed and used as an enlarger lens. It is not the same mount as the later C lenses.

C3 / 33mm Thread
reg - 41.9mm
dia - 33mm

Geiss Mount
reg - 44.5mm

Argus 21
reg - 39mm
dia - 38mm
Altix
Altix made cameras from 1938-1958

Altix Bayonet
reg - 42.5mm
dia - 34mm
Cine Mounts
Still Camera Mounts
Bronica

Bronica ETRS
reg - 69mm

Bronica SQ
reg - 85mm
dia - 78mm

Bronica GS-1

Bronica S2A
reg - 101.7mm
dia - 57mm

Canon 'new' FD
reg - 42mm
dia - 48mm

Canon FL
reg - 42mm
dia - 48mm

Canon EF
reg - 44mm
dia - 54mm

Canon Rangefinder
reg - 28.8mm
dia - 39mm

Canon XL

Canonflex R
reg - 42mm
dia - 48mm

Canon EF-m
reg - 18mm

Canon EF-S
reg - 44mm

Canon R

Canon VL
reg - 20mm
dia - n/a
Contax / Zeiss Ikon

Contax Rangefinder
reg - 34.85mm
dia - 44mm

Contaflex

Contax/Yashica
reg - 45.5mm
dia - 48mm

Contarex
reg - 46mm
dia - n/a

Contax G
reg - 29mm
dia - 44mm

Icarex
reg - 48mm
dia - n/a

Werra
reg - 54mm
dia - 44.5mm

Contax N
reg - 48mm
dia - 55mm

Contax 645
reg - 64mm
Exakta

Exakta Bayonet
reg - 44.7mm
dia - 38mm

Exakta
Fuji

Fuji X Digital
reg - 17mm
dia - n/a

Fuji G690BL

Fuji GX680

Fuji X-Fujinar
reg - 43.5mm
dia - 49mm

Fujifilm G
reg - 26.7mm
KMZ

Start
reg - 42mm
Hasselblad

Hasselblad H
reg - 61.63mm
dia - n/a

X-PAN
reg - 34mm
dia - 46mm

Hasselblad V
reg - 74.9mm
dia - 69mm

Hasselblad 1000F
reg - 82.1mm
dia - 78mm

Hasselblad XCD
reg - 20mm
Konica

Konica AR
reg - 40.5mm
dia - 47mm

Konica F
reg - 40.5mm
dia - n/a
Kamera Werke

Praktina
reg - 50mm
dia - 46mm

Praktiflex m40
reg - 44mm
dia - 40mm x 1mm thread
Kodak

Retina Reflex DKL
reg - 45.7mm
dia - n/a

Kodak C

Kodak M

Kodak S
Kiev

Kiev 10/15
reg - n/a
dia - n/a

Leica R 1cam
reg - 47mm
dia - 49mm

Leica R 2cam

Leica R 3cam

Leica R 3rd

Leica R ROM

Leica TL

L39mm Thread
reg - 28.8mm
26 tpi

Leica Visoflex

Leica SL
reg - 19mm

Leica S
reg - 53mm
dia - n/a

M Digital
reg - 27.8mm
dia - 44mm
Mamiya

Mamiya 645
reg - 63.3mm
dia - 62mm

Mamiya 6

Mamiya 7
reg - 57.85mm
dia - 49mm

Mamiya E
reg - 43.5mm
dia - 49mm

Mamiya 645AF

Mamiya TLR

Mamiya 645N

Mamiya RZ
reg - 105mm
dia - 60mm

Mamiya RB
reg - 112mm
dia - 60mm
Miranda

Miranda
(44m Screw & Bayonet)
reg - 41.5mm
dia - n/a
Miranda's lens mount was originally a 44mm screw mount.. They switched to a bayonet mount for the Sensorex. Some of their lenses have both mounts so they can be used with any Miranda body.
Meopta

38mm Opema
reg - 28.8mm
dia - n/a
Do not confuse this mount with a Leica 39mm mount. They are not compatible.
Minolta

Minolta AF Digital
reg - 44.5mm
dia - 49.mm

Minolta Vectis
reg - 38mm
dia - n/a

Minolta SR / MD
reg - 43.7mm
dia - 41mm

Minolta AF A
reg - 44.5mm
dia - 49mm

Nikon F (Non Ai)
reg - 46.5mm
dia - 44mm

Nikon Ai

Nikon AiS

Nikkor AF

Nikonos

Nikon IX Pronea

Nikon RS

Nikon 1
reg - 17mm
dia - 40mm

Nikon AF-S
Olympus

Olympus OM
reg - 46mm
dia - 46mm

OM AF
Based on OM mount.

Olympus Digital E

Micro 4/3
reg - 38.67mm

Ace
reg - 38.67mm

Olympus PEN
reg - 28.95mm
dia - n/a

Olympus Digital PEN

M37
Rare

M42 semi auto
(aperture lever)
reg - 45.46mm
thread pitch 1mm

M42 Screw
reg - 45.46mm
thread pitch 1mm

Pentax K
reg - 45.46mm

Pentax KAF
reg - 45.46mm

Pentax KAF2
reg - 45.46mm

Pentax KAF3
reg - 45.46mm
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Pentax Q
reg - 9.2mm
dia - n/a
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Pentax 110
reg - 27mm
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Pentax 6x7 MF
reg. - 85mm
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Pentax 645 MF
reg - 70.87mm
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Pentax 645 N AF
Petri
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Petri Bayonet
reg - 45.5mm
dia - 43mm
Petri only made one lens mount, but they also used M42 mounts. Some Petri lenses have Pentax K mounts but they were made by third party manufacturers such as Cosina. Petri bayonet and M42 mount lenses were excellent. The Cosina made lenses are not the same build quality but the optics can be quite good.
Pentacon/Praktica
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Pentacon 6
reg - 74.1mm
The Pentacon 6 mount was developed by Zeiss. Variants of the mount were used by Kiev 88 and Exakta 66.

Praktica B
reg - 44.4mm
dia - n/a
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Pentina
reg - 54.95mm
dia - n/a
Reflex Korelle
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Reflex Korelle
The Reflex Korelle mount is a 40.5mm screw mount for 6x6cm medium format cameras.
Rectaflex
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Rectaflex Bayonet
reg - 43.4mm
dia - n/a
Ricoh

Ricoh 999
reg - 45.5mm
dia - n/a
Rollei

Rollei SL66
reg - 102.8mm
dia - n/a

Rollei SLX
reg - 74mm
dia - n/a

Rollei 2 pin

Rollei 1 pin QBM
reg - 44.6mm
dia - 46mm
Robot

26mm Thread
reg - 31mm
dia - 26mm
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Robot Bayonet
reg - 31mm
dia - n/a
Sony
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Sony E
reg - 18mm
dia - n/a

Sony Alpha
reg - 44.5mm
dia - 49.7mm

Sony FE
Sigma
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Sigma SA
reg - 44mm
dia - n/a
The Sigma mount has two variations. The first version has two bayonets to support heavy lenses. That feature was not actually used so they removed the extra bayonet with the introduction of the SD14. All Sigma AF bodies use the Sigma bayonet mount. Early Sigma MF bodies used Pentax mounts.
Topcon
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Topcon RE
reg - 44.7mm
dia - 38mm

Topcon / Exakta
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UV Topcor
reg - 55mm
dia - n/a
Samsung

Samsung NX
reg - 25.50mm

NX Mini
reg - 6.95mm
Voigtlander

Bessamatic
reg - 44.7mm
dia - 47mm
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Vitessa T
reg - 44.7mm
dia - 47mm
Voigtlander mounts are Deckel mounts. They are the predecessors of the Retina Reflex DKL mount. Info here.
Yashica

Pentamatic
reg - 43mm
dia - 47mm
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Yashica AF
Wirgin / Edixa
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m42 (modified)
reg - 45.46mm
thread pitch 1mm
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m42 (modified)
reg - 45.46mm
thread pitch 1mm
The Edixa m42 mount is oriented slightly off of the Praktica standard. Lenses with aperture arms and automatic aperture lenses made by other mfg's will not work properly on an Edixa body. Also, Edixa lenses may not work properly on standard m42 bodies.
Interchangeable Mounts

T4 Mount
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Vivitar TX
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T-Mount & T2
reg - 55mm
width 42mm
thread pitch .75mm
Vivitar TX mounts look very similar to T4 mounts but they are not fully interchangeable. T4 mounts can be used on TX lenses but TX mounts can not be used on T4 lenses. TX mounts have slightly better automation.
T-Mounts thread onto telescopes, mirror lenses and preset lenses. They do not offer any automation. T2 mounts are adjustable T-Mounts.

Tamron Adaptamatic

Tamron Adaptall
Tamron Adaptamatic mounts attach to the lens a bit awkwardly and are tightened to the lens by way of a large retaining ring. Adaptamatic mounts offer limited automation and can be tricky to attach. Tamron replaced the Adaptamatic with the Adaptall system which offers more control and is much easier to attach.
.jpg)
Sigma YS
reg - 55mm
Sigma YS mounts are basically T-mounts with an aperture pin. They are adjustable and must be adjusted to achieve proper alignment of the aperture pin.
NOTE: Don't mistake T-mounts, T2 mounts and YS mounts for M42 mounts. They are all 42mm but M42 has a different thread pitch. They are never compatible with each other.
Komura used two interchangeable mount systems. The first was a 47mm threaded adapter similar to a T-mount. It is called a Unidapt. Do not confuse this with a rare Tokina adapter which is also 47mm. The second system is called Uni Auto. It is a bayonet system similar to Tamron Adaptall. Both adapters can be very hard to find. This pic was borrowed from a forum.

Komura Uni Auto
reg - n/a
dia - 47mm thread

Tokina 47mm
reg - 55mm
dia - 47mm x .75 tp
Tokina lense, made in the 1960's, used an interchangeable mount similar to a T-mount. The mount was 47mm threaded. Don't confuse it with a Komura 47mm mount. These lenses and mounts are rare. These are also called Hanimex H mounts.

Tokina 47mm mount
Very Similar to Komura
Topman made lenses in the early 1980's. They used an aperture specific interchangeable mount. These mounts are rare but not in high demand,.

Topman Adapter
reg - n/a
dia - n/a
Aaton
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Aaton
Arri
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Arri Bayonet
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Arri PL
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Arri LPL
B4
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B4
BNC
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BNC
Bolex

Bolex SBM
C
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C
1" diameter
32 tpi
reg - 17.526mm
CS reg 15.526mm
D
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D
3/4" diameter
32 tpi
reg 12.29mm
Eclair
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CA-1
Eyemo

Eyemo

Camera
Mitchell
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Standard
4 hole 8mm
3 hole 16mm
Movikon
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Movikon