Adapter guide
Olympus OM lenses on Canon RF
Yes, this works. Olympus OM has a 46mm flange distance and Canon RF mount has 20mm, so a 26mm mechanical adapter with no glass fills the gap and infinity focus is preserved. Focus and aperture stay manual.
- Olympus OM flange
- 46 mm
- Canon RF flange
- 20 mm
- Adapter thickness
- 26 mm
- Optical elements
- None required
Setting it up
Enable Release shutter w/o lens and turn on MF peaking. Canon APS-C bodies use a 1.6x crop rather than the 1.5x of other systems.
Automatic diaphragm with the aperture ring at the front of the lens, next to the filter thread. Many Zuiko lenses carry their own depth-of-field preview button.
Olympus OM lenses and their field of view on Canon RF
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 | Full frame | Frames like (APS-C (1.6x)) | Years | Used value |
|---|---|---|---|---|---|---|
| Olympus OM-System Zuiko Auto-S 50mm f/1.4 | 50mm | f/1.4 | 50mm | 80mm | 1972-1980s | $70 to $280 |
| Olympus OM-System Zuiko Auto-S 55mm f/1.2 | 55mm | f/1.2 | 55mm | 88mm | 1972-1984 | $300 to $900 |
| Olympus OM-System Zuiko Auto-W 24mm f/2.8 | 24mm | f/2.8 | 24mm | 38mm | 1975-1980s | $90 to $300 |
Frequently asked
Do Olympus OM lenses work on Canon RF cameras?
Yes. A plain Olympus OM to Canon RF adapter works with no optics. Olympus OM has a 46mm register and Canon RF mount has a 20mm register, so the adapter is a 26mm tube that puts the lens exactly where a Olympus OM body would. Plain adapter ring. Turning the front aperture ring stops the lens down directly on an adapter.
Do Olympus OM lenses focus to infinity on Canon RF?
Yes. Because the adapter restores the native 46mm 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 Olympus OM lens become on Canon RF?
On full frame Canon RF bodies (EOS R, RP, R3, R5, R6, R8) the focal length is unchanged: a 50mm lens frames as a 50mm. On APS-C (1.6x) Canon RF bodies (EOS R7, R10, R50, R100) a 50mm lens frames like a 80mm lens on full frame; the aperture and depth of field at a given distance do not change.
More on this mount: Olympus OM mount reference