topic Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body. in EF & RF Lenses

70-200 (EF lens with adapter) AF not working on R6 Mark II body.

kcush — Mon, 09 Feb 2026 12:58:08 GMT

Hi there - I am hoping someone out there can help me with a problem I had Saturday night shooting an event. My 70-200 lens on my r6 Mark II body would not autofocus whatsoever. It wasn't even trying to focus. The orange box was there indicating it wasn't focused but the actual AF wasn't doing anything. I decided to see if it worked on my other body and it did. I switched the bodies again this morning to the original way I had them saturday night and the AF now works. I am not sure what happened, but of course this was a panic moment for me. Any insight is appreciated.

Kellie

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

shadowsports — Mon, 09 Feb 2026 13:28:12 GMT

Greetings ,

Sounds like a communication problem between the camera and lens. This could be related to the adapter or the sequence in which it was mounted.

There really isn't a way for us to do anything but speculate. it's working now and we can only guess if you can't reproduce the problem. Sorry. 🫤

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

kcush — Mon, 09 Feb 2026 13:39:05 GMT

Thank you! yeah it was weird. I need to just bite the bullet and buy the RF lens, but spent about $7000 last year on upgrading the bodies and getting a new 24-70 RF lens. Thanks for the reply!

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

justadude — Mon, 09 Feb 2026 14:23:10 GMT

I don't know that you need to buy the RF version. I have the older EF version and it has worked very well on my RP, R8, and R6 Mk ll. Have you tried to clean the contacts? Do you have a local camera shop you can bring both in to and have them test the lens on another body both with YOUR adapter, and maybe also with an in-store one? Last question is your adapter Canon brand? While most third party adapters are fine, I know that some have problems.

I'm simply suggesting these things because the EF 70-200mm works beautifully on the R6 Mk ll.

One last suggestion just in case it's something to do with your AF settings. Watch this video interview with Canon legend Rudy Winston. He covers everything with the Canon AF system. Even guys like me that have been shooting for decades learn a few things we didn't know on this video.

https://www.youtube.com/watch?v=eIxK8B-_Kn8

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

jrhoffman75 — Mon, 09 Feb 2026 14:33:33 GMT

Mount the adapter to the lens before you mount the assembly on the camera.

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

kcush — Mon, 09 Feb 2026 14:37:24 GMT

This is all very helpful! I will watch the video and yes, planned to run my camera to my local shop to see if they can diagnose it. Wanted to see if anyone here has had the same issue ever. I did try cleaning the contacts as well Saturday night.

Thanks Gary!

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

kcush — Mon, 09 Feb 2026 14:37:13 GMT

yeah that's what I've done - but will try again if it happens. It seems just fine now, which is also why I'm so perplexed. Thanks John!

Re: 70-200 (EF lens with adapter) AF not working on R6 Mark II body.

ebiggs1 — Mon, 09 Feb 2026 16:04:10 GMT

" Have you tried to clean the contacts? " " I did try cleaning the contacts as well Saturday night."

And as you have seen that rarely to never (way more on the never side) helps or works. The fact of removing and mounting lenses is generally enough to keep the contacts clean enough to work properly. And if the cleaning is done incorrectly you can do permanent (as in not repairable) damage to them. There is a micro thin gold plating that doesn't take much to damage it.

Rick is right, "There really isn't a way for us to do anything but speculate."