R5c aperture fluctuates in video mode

[cwilson]

This just started happening recently:

Using a canon RF>EF adapter (we've tried both the regular one, and the ND one) in video mode the camera will occasionally not be able to keep the lens in any aperture other than all the way open. If you try and close it down it repeatedly cycles between wide open and your desired aperture, constantly opening and closing the blades.

I've tried restarting the camera, pulling the battery, multiple canon EF lenses, different RF>EF adapters, and I've updated to the latest firmware. I can't test with an RF lens because I don't have one (but having it happen with multiple adapters and lenses tells me its probably the camera body at fault).

I've attached a video to demonstrate the issue. 

[cwilson]

Still no solution. I sent it to them to assess, and they said they were unable to replicate the issue. They updated the firmware, but the unit still *occasionally* has this problem. I've sent this r5c back to them for another issue, and asked that they test it again. Even supplying the video the techs replied they were unsure what I was asking, so I don't have high hopes. I'm not amazingly impressed with the build quality on this camera, but for the price and features I'll put up with it.

[shadowsports]

Sorry I am not able to reproduce this either, with my current RF or EF Canon lenses or previous Sigma  24-70 f2.8.  Worth noting, the sigma was sold before the release of 1.0.5.1.  So I was only able to test with 1.0.3.1.  

It's a very odd behavior, the aperture is jumping wide open between clicks instead of remaining stopped down and moving to the next selected stop.  This is not expected in manual mode.  Hopefully Canon can figure this out for you.