R5 Auto ISO - a bug or intended behavior?

[Cytography]

I just discovered an interesting behavior with my new R5 related to AUTO ISO. For sake of discussion, assume I’m in Av mode (haven’t tested this behavior in other modes). Using the Quick Control Dial #2 (the thumb wheel surrounding the Mode button), the default behavior is for that control to allow adjusting ISO. But, quite by accident, I discovered that if I use that dial to set ISO to something other than AUTO and then engage metering (either with half shutter press or back button focus) then I can’t set ISO back to AUTO for some number of seconds. This is true whether or not I take a picture.

The amount of time I must wait to be able to go back to AUTO ISO (using the control dial #2) seems to be tied to tied to the time set in “metering timer” on camera (red) tab 7. However, if I go into the menu at Camera (Red) tab 2 >> ISO settings I can override this time delay and immediately put the camera back to Auto ISO.

This behavior is different than my 5D Mark IV. On that Camera, regardless of how I have the metering timer set, I can always press the ISO button and turn the appropriate thumb wheel and immediately set ISO back to AUTO.

Is anyone else experiencing this seemingly unusual behavior? Is it possibly a bug, or might I have some setting somewhere set that is causing this behavior.  I'm thinking possible bug since my 5D IV doesn't behave this way.

[Waddizzle]

Have you tested this behavior in other modes, yet?

I would also be curious to know the setting you are using for “Continuous AF” and “Safety Shift”.

[Cytography]

Same behavior in Tv and M modes.  Continuous AF is disabled and Safety Shift is Off.

[amfoto1]

I'm just guessing, but...

Do you have "AE-Lock" selected or enabled on the R5 and not on the 5DIV?

AE-Lock is used to take a meter reading and lock the exposure, then be free to recompose without changing those settings for a short period of time. I don't have either of those cameras, so don't know how long AE-Lock holds the settings after the metering, but seem to recall it's about 15 seconds on some Canon cameras I've used.

On many Canon cameras pressing the * button that temporarily activates AE-Lock.

But it is possible to set up the camera to always use AE-Lock, for every exposure. One way I recall was when setting up back button focusing on some cameras, one of the options is to use AE-Lock full time.

P.S. I have no idea why this started double spacing between lines or how to make it stop doing so. Sorry!  

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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
FLICKR

[Cytography]

That's a good question but, no, I'm not engaging :AE-lock.  In fact I have the * (AE-Lock) button reassigned to be eye AF.

[amfoto1]

Okay, you aren't manually selecting AE Lock and, in fact, have reassigned the asterisk button to other function...

Still, there are other ways that AE Lock can be activated. Next time you use your camera, look in the lower, left hand corner of the viewfinder. If you see the asterisk there, AE Lock is enabled. Why, I can't be sure... perhaps because of button reassignments you've made or something else changed in the menu.

I don't use AE Lock a lot myself. But I believe it can be cancelled manually by pressing the AF Point Selection button... So that's something else you can try, next time you see this situation with your camera.

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
FLICKR

[Waddizzle]

Another way to lock exposure is through locking an AF point prior to firing the shutter.

In One Shot AF mode, this means the exposure is locked when an AF point is locked.  This is what “focus and recompose” was all about.  A half-press should lock in the exposure until the metering timer expires, or if you release the half-press.

In Servo AF mode, the exposure is locked just prior to the shutter firing, which when you fully press the shutter button.

[jaewoosong]

I see the same behavior in AV mode.  I've bumped that dial and switched to ISO 100 indoors once and wondered why my shutter speed was all of a sudden slow.  Never had problems with my 5DmIV because that camera didn't have that dial.  I debated disabling that particular dial but I just got used to checking for the auto iso if my shutter speed doesn't seem right.

[FloridaDrafter · Accepted solution]

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@Cytography wrote:Is anyone else experiencing this seemingly unusual behavior? Is it possibly a bug, or might I have some setting somewhere set that is causing this behavior.  I'm thinking possible bug since my 5D IV doesn't behave this way.

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Yes, it works that way on my R5 and R6. You don't have something set wrong, and our cameras are set up very modestly, so I can say that with confidence. I don't think it's a bug, but could be an oversight, however I do see the logic in the way it's tied to metering. It could just be the way MILC's work or a limitation although I don't see why.

We don't use auto ISO, but I just went through my books and the cameras looking for a solution. With metering tied to ISO, at this point, you just have one option, and that is to set the meter to four seconds and make do the best you can. I did find a menu where I think the option you want should be, and that is the third option in "Custom Functions Settings", menu one, "Speed from metering/ISO Auto". In that sub menu, you can set "Restore Auto after metering" or "Retain speed after metering". IMHO, there should be a "Restore Auto after shot" or something to that effect.

This might be a good one to submit to Canon Support as a request.

Newton

[Cytography]

Yes, I too haver concluded that this is "normal" as-designed behavior.  It's not a huge deal, but I just find it odd that I can't over ride that delay and just instantly put the camera back into Auto ISO if I want to without the need to wait.