Common Mounts
and Adapters


This list doesn't include every known mount, but does include the common lens mounts that are seen out there. The number of adapters available on eBay has increased dramatically in the last few years.

Explanation of units:

tpi = threads per inch
M25 = 25 mm diameter (M = metric)
Second number such as 0.75 = 0.75 mm per thread

RMS (0.8 inch x 36 tpi)

Applications: Older microscope objectives, bellows lenses.
Adapts to: C-mount, M25, M26, M27, M39, T-mount, M42, Camera specific, and 52 mm filter thread.

Microscope specific mounts (M25 x 0.75, M26 x 0.7, M27 x 0.75):

M25 x 0.75: Leica, Nikon Biological
M26 x 0.7: Mitutoyo, Olympus BD, Nikon BD
M27 x 0.75: Zeiss
Applications: Many newer microscope objectives.
Adapts to: RMS, C-Mount, M39, M42, 52 mm filter thread

Schneider 00 (M25 x 0.50)

Applications: Small, short focal length enlarging lenses.
Adapters: M39, M42.

C-mount (1 inch x 32 tpi)

Applications: Video lenses, CCD cameras for microscopes.
Adapters: T-mount, camera specific

M29.5 x 0.5

Applications: Schneider M-Componon lenses
Adapters: M39, M42

Schneider 0 (M32.5 x 0.5)

Applications: Some enlarging lenses
Adapters: M39, M42

Leica screw mount (M39 x 1)

Applications: Enlarging lenses, old photography lenses, a few bellows lenses.
Adapters: T-mount, M42, Camera specific.

T-mount (M42 x 0.75)

Applications: Old photographic lenses, spotting scopes, telescopes.
Adapters: Camera specific

Pentax screw mount (M42 x 1)

Applications: old photographic lenses, a few bellows lenses.
Adapters: Camera specific

Camera specific mounts

Camera EF FD MA MD F OM 4/3 M42 K SA
Canon EF (current) -- + + + + 5 + +
Canon FD -- + +
Minolta A (current) -- + + + + --
Minolta MD 5 -- 5 5 + 5
Nikon F (current) 5 + -- 5 + +
Olympus OM --
Olympus 4/3 (current) 5 + + + + -- + +
Pentax M42 --
Pentax K (current) 5 5 + 5 + --
Sony Alpha (current) -- + + + + --

Guide: + = available, 5 = homemade adapter using cheap 5-piece extension tubes available on e-Bay, -- = same, no adapter needed

Guide to using 5-piece extensions as camera adapters:

The 5-piece extension tubes presently available on e-Bay come in a variety of lens mounts. These are modular units and they all screw together with standard threads. If you get one of these for the lens you want to adapt and one for the camera body you are using you can mix and match the parts. I used the Nikon F-mount portion and screwed that onto the female mount for the lens I was adapting. Pretty simple and works well.

I did have a problem with adapting Nikon to Minolta. The parts had the opposite threading. Both the Nikon mount and the Minolta mount had female threads so they wouldn’t screw together. I am not sure if this was because I bought them from two different sellers or if all Minolta have the opposite thread from the Nikon tubes. It would be wise to buy them both from the same seller.

I solved the Minolta problem by getting a 58 mm - 52 mm step-down ring. The 58 mm ring fits into the Minolta portion of the adapter and the 52 mm fits onto my reversing ring. Not so simple but it does work.

Another problem I ran into was adapting Olympus lenses to my Nikon body. This was a little easier to solve. There are 5-piece extensions available for Nikon and Olympus 4/3 mounts available on e-Bay. These screwed together without trouble. Since the Olympus lens is an older OM mount, I had to get an additional OM to 4/3 adapter which are easily available.