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R6 auto ISO problem


I usually have my R6 set with Auto ISO on and locked, and I shoot in TV or Aperture mode.  I've noticed on several occasions that when I look through the viewfinder to frame a shot, the view is washed out because the Auto ISO is high, e.g. 25600, even though the weather is bright and sunny. The setting will be stuck at that level and I have to turn the camera off and back on.  This usually happens when I haven't taken a shot for several minutes, typically when the camera has been sitting besides me on the car seat.

What would cause the Auto ISO to jump to an inordinately high level when idle?





Unknowingly pressing the AEL button could cause it.  Safety Shift?

Personally, I only use ISO Auto in M shooting mode.  I never want to allow the camera to control more than one leg of the Exposure Triangle at the same time.

"The right mouse button is your friend."

When this happens, the Auto ISO is still locked. It hasn't become unlocked accidentally. 

If the Auto ISO would correct when I try to frame the picture, there wouldn't be a problem, but when this happens, the ISO is stuck on 25600; it doesn't adjust when I point the camera at the target.

You could try switching out of ISO Auto to a fixed setting, wait a couple of moments, and try to meter a scene, and then switch it back to ISO Auto.  I would not switch to ISO Auto in Tv or Av modes.  I would switch out of ISO Auto, and leave it that way for Av and Tv modes.  

Personally, I prefer shooting in M mode with ISO Auto, and programming the [SET] button for Exposure Compensation.

"The right mouse button is your friend."

Thanks, but in the time it would take to do what you suggest, I could simply turn the camera off and back on.  I'd like to what causes the problem.

I shoot wildlife, particularly birds, and I often don't have time to change settings when the opportunity to take a picture occurs.  That's why I usually have the ISO locked on Auto.



The EOS R6 features focus bracketing, which lets photographers create focus-stacked composite images with much more depth of field than can be generated with small apertures alone. It's an especially useful technique for close-up or macro images, where depth of field is naturally shallow.

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Not sure what that has to do with the Auto ISO problem.


I have experienced on multiple occasion the AUTO ISO (while in Manual) on an R5 inexplicably getting stuck in a very low setting ISO, e.g. 100 or 160.  Even taking the batteries out doesn't seem correct it, the camera just has "to decide" to start behaving properly...extremely annoying for photojournalism type photography.


I had the same problem a few days ago with R6 suddenly going to 125000   I was trying to photograph a group of friends and quickly turned camera off and on with no change and then pulled the battery out with no change.  I then used my iPhone!   Later I limited the ISO range but I’m not certain I had it on auto to begin with.  Now I have it off ISO auto. Later in the day the camera jumped to a very low shutter setting (ISO at 320), washing out a picture.  What’s going on?  I’ve been shooting with many cameras over fifty years with all vintages of Canon and Nikon SLRs, DSLRs and mirrorless and never had this happen.  I haven’t found that inadvertently pressing the rear buttons has any effect.  Perhaps Canon needs to look into this. I was afraid my camera was faulty and was glad to find this conversation.