EOS R6 Mark II - Photos in P mode are suddenly going dark.

[FTirrell]

Recently, on two separate occasions (about 3 wks apart), while taking a sequence of 4-6 photos, the screen in the view finder got suddenly dark as if I changed the exposure level while taking the sequence. No changes were made to the settings while taking the shots; and the only thing I could do to get the preview back to a normal view was by turning off the camera and resetting it. Both times, the setting was on Program mode with set ISO.  At first, I thought it was limited to the display but when I downloaded the photos the second time, the first few photos in the sequence were fine; however, the ones that were dark in view finder, were also dark. The only difference in the Meta data I could see was that the exposure time was different - 1/250 for the normal and 1/1000 for the dark one.   I installed the newest firmware.  I am using a Canon EF 28-300mm f/3.5-5.6L IS USM Lens with adaptor with the camera. The Camera/adaptor was purchased in 2024 and the lens in 2023. 

Looking for to see if this a new known issue with the newest firmware or my specific camera 

Frank

[Waddizzle]

We are going to need a few details about your issue.  What type of “sequence” are you trying to perform?

Tell us about your camera setup and settings.  Try tell us how to replicate what you’re doing. 

[FTirrell]

Thanks for replying.  To clarify, when I said "sequence" I should have said a series of multiple shots - not fast bursts but single pressing of the shutter button.   Mode = P and ISO 400 for all shots. Focus Point was set to the further multiple point setting.   See the 2 photos for better explanation and meta data for the four images. The first image shown is an example of how the prior photos appeared in the view finder and how they turned out when downloaded from the memory card. The two center images are examples for when the View finder and image went dark. The last photo is one taken after I turned the camera on/off and operation returned to normal.  Resetting the camera was the only way to get it back working correctly.  I took another 100 or so photos on the same day after resetting and another 700 the next day with no issue.   The first time this issued occurred was about 3 wks ago; however, I don't have the stats for that time since all I did was reset the camera and it returned to normal operations and had no issues for the last couple of weeks. Up till the first occurrence 3 wks, I have never this issue ago. It might only be a coincidence but the first time that the issue occurred was shortly after I updated to the lastest firmware which is why I question if it was possible that it was related or more of a hardware (camera) issue.   

[deebatman316]

Are you using the Canon brand adapter if so which version. Or are you using a 3rd Party Mount adapter. If so discontinue the use of it. They’re known to cause all sorts of problems.

[FTirrell]

I have the Canon Mount Adapter EF-EOS R, which was purchased the same time as when I purchased the R6 Mk II on 5/13/24.  I updated to the latest firmware (1.6.0) around 7.17.25 and took around 1000 photos before the first occurrence happened.  I removed the lens from the mount, and the mount from the camera body and reattached. I have not had a chance to use the camera since I removed and reattached them.  I was thinking about reinstalling the software in case it became corrupted during the initial installment.  

[deebatman316]

Canon has made 3 different EF-RF Mount adapters. So we need to know which exact model you have. Canon has the basic adapter, control ring and drop in filter model adapters. 

[FTirrell]

It is the basic, which Canon has as the "Mount Adaptor EF-EOS R". 

[deebatman316]

Have you tried the lens on a DSLR camera to see if it works properly.

[FTirrell]

No - it only has occurred twice out of taking around 2000 shots, so it is very random when it occurs. If It occurring more frequently, it would be easier to troubleshoot.  I was just wondering if others have experience this. 

[FTirrell]

I have a couple of days of heavy shooting coming up. I will go back and use the lens on my 6D to see if I encounter the same issue which would then narrow the cause to the lens.