EOS R6 Mark II - constantly changes ISO randomly & white balance periodically

[fstopPhoto]

I started using this camera last September (2024) and every single time I use it the ISO randomly changes on its own.  I typically shoot all indoor, low light situations with ISO 3200 - 4000.  Exposures will be fine the suddenly either dark or overexposed.  The ISO might go down to 400 or 640 or up to 12,500 for no reason whatsoever.  This happens multiple times a day, every single day I use it.  I'm ready to throw it out. 

I have turned the return to auto ISO off and this does absolutely nothing.  It's driving me crazy!  Nothing works to change this.  I have set the ISO range to a low of 3200 and a high of 6400, which I don't want it to be that high but that's the only option, set the ISO to 3200 and it will still change ISO to AUTO or to any ISO between 3200 and 6400 for no reason.  

I thought maybe my forearm is touching the screen and somehow changing the ISO, which is hard to believe, so I turn the camera off when walking.  I can turn it back on and the ISO has changed from my original settings.  I can shoot a series of photos and it changes ISO on the next photo.  

I have reset the camera to factory settings.  The firmware is up to date but I downloaded it again and reinstalled the most current firmware and it still does it.

This is absolutely insane and I can't figure out why it's happening or how to get it to stop. 

Every once in a while the white balance will also change randomly but that has only happened a few times in the last 7 months of use, whereas the ISO changes every single day, multiple times a day.  

Any suggestions or Canon employees who can help with this?

Thanks,

Dave  

[Waddizzle]

I am not convinced that the issue isn’t inadvertent user error.  Every description of the problem is consistent with user error, especially the fact that it happens at random.

The earlier post by Brian that included the following screenshot is telling.

 

The ISO has been set to a very limited range, 3200 to 6400.  Note that Auto is an available option.  The ISO Auto option is always available.  The user cannot manually increase the ISO above 6400.  However, the can decrease the ISO to 3200, and one more click of the dial will set ISO Auto. 

As Brian further points out, once ISO is set to Auto, the available range of available ISO settings is defined by a different setting! 

The issue can also manifest itself when using a custom shooting mode.  The camera body has been sent out for repair, only to be returned with no electronic or mechanical issues found.

[fstopPhoto]

Nope.  I started setting the range to that because I was getting swings from 3200 to 400 to over 8,000 in between shots.  It's not "user error."  The camera is **bleep**.  Once again, I've had the camera change ISO from 3200 to 4000 to 5000 over 5 consecutive shots taken in 13 seconds with the camera up to my eye not touching anything but the shutter button.  I watched the ISO change to AUTO while the camera sat untouched on a table.  It's the camera, not me.  I've used at least 5 different Nikon film cameras, 3 Bronica medium format cameras, a Nikon D100, Canon 30D, Canon 1D Mark II, Canon 5D Mark III among others and this is the ONLY camera that has ever had this much trouble.   I literally took a few photos of 2 people at ISO 3200, turned 90º and took a photo of 2 other people and watched the ISO change to 6400 in the viewfinder without touching anything but the back button focus and the shutter button.  The problem is clearly in the AUTO ISO feature and it appears turning off the return to auto feature just doesn't work.  The camera has a mind of it's own. 

[Waddizzle]

“ I've had the camera change ISO from 3200 to 4000 to 5000 over 5 consecutive shots taken in 13 seconds with the camera up to my eye not touching anything but the shutter button.“

Making lots of loud noises has gotten you nowhere. Help someone to help you.

I ask you to post the examples.  You have been asked previously to post an example, and you declined.  Be sure to include the EXIF data.  It would be most helpful if you could upload RAW files to a public file sharing platform like Dropbox.

Again.  Seeing the ISO display switch from a value to “Auto” is entirely consistent with the camera being set to ISO Auto. 

[sbsox]

Hi Dave,

That definitely sounds frustrating. Since you’ve already reset to factory settings, updated the firmware, and ruled out Auto ISO, it might be worth checking a couple of things:

1. Custom/Personalized Buttons – Sometimes the ISO dial or multi-function buttons get accidentally assigned to ISO control. If your hand brushes them while shooting, ISO might jump around. Double-check your button customization settings.

2. Touch Screen Sensitivity – Even if you don’t think your arm touches it, the screen can be overly sensitive. You can either disable “touch for settings” or set it to “tap only” instead of “drag.”

3. Mode Dial Lock – Make sure the shooting mode dial isn’t slipping. On some units, a loose dial can cause exposure shifts that look like ISO changes.

4. Hardware Issue – If none of the above helps, it may actually be a hardware problem with the ISO control dial or internal circuitry. At that point, I’d recommend sending it to Canon support for a check-up.

I totally get how annoying this is — I shoot a lot indoors myself (long sessions can be as uncomfortable as wearing the wrong gear… which is why I swear by light weight compression socks  to keep me comfortable during shoots 😅). Hopefully Canon can give you a more permanent fix so you don’t have to keep fighting with ISO changes.

Good luck — let us know what Canon support says!

[fstopPhoto]

Nobody here has asked me to post samples.  If anyone did I haven't seen the post and I don't see any now, plus another user in this thread is having the same issue and I know another photographer who has the same issue as well, so it's me and it's not us.  Here are the 5 shots taken in 13 seconds with 3 different ISO settings while the camera was up to my eye.  Also attached are 2 photos taken 7 seconds apart where I watched the ISO change from 6400 to 3200 in the viewfinder as I composed the shot.  The camera was up to my eye and I saw it change on its own. I literally turned 90 degrees to take this second shot of 3 guys who were to my immediate left without changing anything and watched it change from 6400 to 3200. THIS IS NOT "USER ERROR"!!!

If I turn the camera off at one ISO and it's set to another ISO when I turn it back on that's not "user error" that's the camera screwing up.  If I have "retain speed from metering" selected and set my own ISO it should NOT change to AUTO while the camera isn't even being touched.  It should not change ISO while the camera is up to my eye and my thumb is on the back button focus and my index finger is on the shutter button and nothing else is touching the screen.  It should not change between 2 shots seconds apart.

I appreciate your efforts in this but you're flat out wrong.  This has been ongoing for a year now since the day I got it. The camera is just screwed up.  

[fstopPhoto]

Thanks, but none of that applies.  I have no custom buttons set except to turn off focus from the shutter button as I use back button focus only.  The fact that I can turn the camera off at one ISO and it's set to a different ISO when turned back on and I've seen it change while the camera is up to my eye negates the touch screen issue. My mode dial is not slipping.  It's stiff and always set to Manual.  Canon has looked at this camera twice and has failed to find the problem.  

[mcoverton]

these were taken one right after the other, I didn't move- clients didn't move, I didn't change settings.  It does this EVERY few minutes.  I'm so done with it.

[JamesHarvey]

If all of you with those issues could show us there two menu screens, please, it would enable us to give you a much more definitive answer (this is from a response earlier in the thread): Thanks! 

[JamesHarvey]

Need the full exif data to help.  Clearly this is jump in Tv that has caused the issue, but there is no ISO gain info in your illustration, nor information on the other exposure controls in the camera. 

[PP2]

Hi, I had the same issue, found a setting you can turn it off. I registered just to tell you 🙂

To disable Auto ISO on the Canon R6, for consistent manual control, go to the Camera (orange) menu 1, then Speed from metering / ISO Auto and set "Retain speed after metering" to OFF. This setting prevents the camera from automatically reverting to Auto ISO after the metering timer expires.