R5 not changing aperture in photo mode

I've recently encountered an issue with my R5 where it doesn't matter what aperture i set it to, the lens will not adjust, and shoots fairly wide open.

I'm currently using the ef-rf adapter with the drop in filter on a 50 L1.2. When in video mode I can see the aperture fins adjust to what the camera is set to so I don't believe this is a lens issue.

I thought I resolved this when I upgraded my firmware, but yesterday during a shoot it happened again. Once it does this I can't seem to get it to get 'unstuck'

Has anyone else encountered this issue? I'm hoping there is a setting that I'm not aware of that is causing this.

In video mode the aperture will stop down and stay constant to support the continuous shooting. In photo mode Canon systems will always focus and meter wide-open and only stop-down when the shot is actually taken. If you look at the lend when pressing the shutter button, that's when you should see the aperture blades closing when taking photos.

That's the issue, it's not closing to the correct aperture.

Lets say I set the aperture to f16, When I take the picture, the result is closer to f/2.8. When I watch the lens when I shoot the photo, the fins aren't closing down to where I'd expect it to be for f/16 either.

But in video mode like you mentioned - since it's constant it appears to be functioning as expected.

dwap said:

That's the issue, it's not closing to the correct aperture.

Lets say I set the aperture to f16, When I take the picture, the result is closer to f/2.8. When I watch the lens when I shoot the photo, the fins aren't closing down to where I'd expect it to be for f/16 either.

But in video mode like you mentioned - since it's constant it appears to be functioning as expected.

Click to expand...

Have you tried contact cleaner on all the contacts of both the lens and the adapter (apply with a brush or the like and not sprayed direction on the contacts)? I know you say it stops down in video mode, but maybe there is a communication problem.

When you say it is closer to f2.8, are you saying that the exposure is totally blown out because the difference should not be subtle?

Karl_Guttag said:

dwap said:

That's the issue, it's not closing to the correct aperture.

Lets say I set the aperture to f16, When I take the picture, the result is closer to f/2.8. When I watch the lens when I shoot the photo, the fins aren't closing down to where I'd expect it to be for f/16 either.

But in video mode like you mentioned - since it's constant it appears to be functioning as expected.

Click to expand...

Have you tried contact cleaner on all the contacts of both the lens and the adapter (apply with a brush or the like and not sprayed direction on the contacts)? I know you say it stops down in video mode, but maybe there is a communication problem.

When you say it is closer to f2.8, are you saying that the exposure is totally blown out because the difference should not be subtle?

Click to expand...

I'll try contract cleaner when I get home.

well, its not just the exposure but the depth of field as well.

It's noticeably extremely shallow. doesn't matter what the aperture is set to, its almost like its just ignoring that setting.

When I take the photo and watch the lens, the fins come out, but just barely, even when the aperture is stopped all the way down.

When I upgraded firmware the problem went away, but unfortunately it's back.

Update: I've narrowed it down to being an issue with just the 50L lens. I tried a couple other lenses and I can't reproduce the behavior.

What I find weird is a firmware update initially fixed this.

I'll probably need to call canon and maybe get the lens serviced but I'm wondering is there a setting on the R5 outside of a factory reset that will let you delete any data stored on a specific lens?