Loose Lens with Olympus OM to Canon EF Adapter?

HansPhotography13 Comments

Recently, I bought two manual focus Olympus OM lenses on eBay, the 50mm f/1.8 and 28mm f/3.5. Nothing spectacular, but I was impressed with the optical quality, and solid build of these lenses, they’re just good bang for the buck. Yes, the Olympus OM 50mm f/1.8 is perhaps even better than the Canon 50mm f/1.8!

The day after, I ordered some OM to EF mount adapters with focus confirmation from BIG_IS. The focus confirmation works fine, however, I noticed that when I attached the lens to the adapter, the lens was slightly loose on the adapter and could move around a bit while focusing.

I contacted the seller about it and learned this little hack: There are three small grooves on the adapter’s mount, if you use a tiny screwdriver to widen these grooves just a little bit, the OM lens will fit the adapter more tightly. Be careful though, don’t widen them too much or it’ll be very hard to dismount the lens from the adapter again. See the image below, it works!

Olympus OM to Canon EOS EF Adapter

HansLoose Lens with Olympus OM to Canon EF Adapter?

13 Comments on “Loose Lens with Olympus OM to Canon EF Adapter?”

  1. Ashley Pomeroy

    I want to give you a big hug for this. The picture is very handy.

    I have the same problem with two different OM-EOS adapters – the lenses fit into my OM-10 perfectly, and the adapters fit on my Canon bodies just as well, but the lenses shift around in the adapters as I focus. A quick go with a screwdriver and they are not solid as a brick.

    I assume the grooves get bent back into shape as the lens is mounted and re-mounted, but on the other hand I could just get several adapters and leave them on each lens.

  2. Graham

    Just used this to fix exactly the same issue on my E-P1 to EOS adapter. Great would never of thought how to do it without your help. Thanks.

  3. Katharine @ Olympus Discount

    Hi, just browsing for information for my Olympus site. Amazing the amount of information on the web. Wasn’t exactly what I was looking for, but good site. Have a great day.

  4. Lynn

    I have just the opposite problem … I bought an Olympus OM lens on ebay, and when it showed up it had an EOS adaptor on it. And I cannot get it off. Absolutely no play, and pressing the lens release button doesn’t help. Suggestions? Thank you.

  5. Hans Doddema

    Lynn, that sucks. I have an adapter that will probably never go off again as well. Any chance of bending the adapter? A lubricant? I’d just contact the seller first, though.

  6. Cian

    I hope your happy, you’ve made my day! My Zuiko 300mm now fits perfectly on my Canon Eos 1n.

    Thank you very much

  7. Jon


    This sounds like a great tip but also, I find that the lens rotates slightly with my Big Is adapter – does anyone else find this?

  8. Harold Gough

    Removing tightly-fitting adaptors might work on the following principle: Cool the whole unit as much as you dare, (place lens in fridge). Then, before it can warm up, apply gently heat to only the adaptor and twist it to remove. The idea is that metal expands when heated and the outer metal will expand first and so become loose. (This also works well with tight lids on jars of preserves, where hot water on the lid loosens it from the cooled jar).

Leave a Reply

Your email address will not be published. Required fields are marked *