RF 100-500 on R7 AUTO ISO issue. Is it normal?

[kepAE1]

I purchased the Canon RF 100-500mm lens last week. I have had several days now trying to get used to it with my Canon R7. (Was using the Tamron 100-600). I have an issue that am not sure it is a defect or normal.

When using AUTO ISO in any mode (NOTE: that I always shoot in manual), when I change the zoom and refocus, the ISO setting becomes frozen at some apparently random number. I have to reset AUTO ISO (done easily via the ISO button), to force camera/lens back to AUTO ISO function. In the instruction manual it mentions that you will likely need to refocus after changing zoom, but there is no mention about AUTO ISO. Kind of a pain when trying to capture fast moving wildlife.

Any help?

[Waddizzle]

Welcome!

What Metering Mode are you using?  I would recommend using Evaluative Metering Mode for almost everything.   

[kepAE1]

Yes, I use Eval.

[p4pictures]

Are you using back button AF with the AF-ON button? Is it possible that when you press the AF-ON that you are also pressing the AE-lock button next to it? This would lock the ISO for about 10 seconds, and you'll see an asterisk in the lower left corner of the LCD and EVF. 

If you have done a lot of customised controls I would try using the camera in A+ mode as this ignores all customisation, then if the problem goes away you know it's something to do with the customised buttons.

[kepAE1]

UPDATE:  The vendor's tech agreed with me that this issue was not normal. Since other lens work OK with the same settings, we thought the lens was the issue.  He arranged for an exchange of the new lens. Just got the new lens.  Same issue, so problem must be with the Canon R7 which is just beyond warranty. Guess I will need to talk to Canon Support to see if I a missing something, else will have to decide to live with the issue or send camera in fro repair.