Adapter guide
Contax/Yashica lenses on MFT
Yes, this works. Contax/Yashica has a 45.5mm flange distance and Micro Four Thirds has 19.25mm, so a 26.25mm mechanical adapter with no glass fills the gap and infinity focus is preserved. Focus and aperture stay manual.
- Contax/Yashica flange
- 45.5 mm
- MFT flange
- 19.25 mm
- Adapter thickness
- 26.25 mm
- Optical elements
- None required
Setting it up
Enable Shoot w/o Lens (Panasonic) or leave Release Priority on (Olympus and OM System), then enter the focal length for in-body stabilisation. The 2x crop doubles the apparent focal length, so a 50mm frames like a 100mm.
Automatic diaphragm. C/Y lenses sit at the set aperture when off the body, so the ring works directly on an adapter.
Contax/Yashica lenses and their field of view on MFT
Effective focal length changes with sensor size. The lens itself does not change; the smaller sensor simply captures a narrower part of the image circle.
| Lens | Focal length | Aperture | Frames like (Four Thirds (2x)) | Years | Used value |
|---|---|---|---|---|---|
| Carl Zeiss Distagon T* 28mm f/2.8 (C/Y) | 28mm | f/2.8 | 56mm | 1975-2005 | $180 to $550 |
| Carl Zeiss Planar T* 50mm f/1.4 (C/Y) | 50mm | f/1.4 | 100mm | 1975-2005 | $120 to $420 |
| Carl Zeiss Planar T* 85mm f/1.4 (C/Y) | 85mm | f/1.4 | 170mm | 1975-2005 | $500 to $1,400 |
Frequently asked
Do Contax/Yashica lenses work on MFT cameras?
Yes. A plain Contax/Yashica to MFT adapter works with no optics. Contax/Yashica has a 45.5mm register and Micro Four Thirds has a 19.25mm register, so the adapter is a 26.25mm tube that puts the lens exactly where a Contax/Yashica body would. Plain adapter ring, no mechanism required. Zeiss and Yashica ML lenses share the mount and use the same adapter.
Do Contax/Yashica lenses focus to infinity on MFT?
Yes. Because the adapter restores the native 45.5mm register, infinity focus is preserved and the full focus scale on the lens stays accurate. Adapters machined slightly short let the lens focus past infinity by a small margin, which is harmless; adapters machined long stop short of infinity, so buy from a maker with tight tolerances.
What focal length does a Contax/Yashica lens become on MFT?
On Four Thirds (2x) MFT bodies (Lumix G, GH, GX; OM-D and PEN; OM-1 and OM-5) a 28mm lens frames like a 56mm lens on full frame; the aperture and depth of field at a given distance do not change.
More on this mount: Contax/Yashica mount reference