Shutter/ISO limits in expo lock

[Audionut]

Never really noticed how useful expo lock was before.

First thing I thought was that I can ETTR, and then adjust DOF while maintaining exposure.  That's pretty cool.

Can you add minimum shutter and possibly maximum ISO limits please.  I'm not sure what's the best way to handle hitting both limits simultaneously.

[a1ex]

Maximum ISO is the one from auto ISO in the menu, but it's not really a limit (it only gives priority to the other setting).

Minimum shutter... I can't see why anyone would use that. If you want more motion blur, just dial a slower shutter.

[Audionut]

Lets say I want a minimum shutter for handheld requirements etc.

I can dial in an exposure at wide open aperture.  If I want to quickly change DOF, I could do so with expo lock, while maintaining exposure. 

But I need a minimum shutter setting to ensure I don't end up with a shutter speed below what the situation requires.  Without a minimum shutter speed, this sort of defeats an advantage of expo lock, quick changes to DOF at the same exposure.  Currently, if the shutter drops below minimum requirements, it requires further user intervention to correct.

IMHO, this beats Av mode (easy), and it's also better then AutoETTR.  As with an exposure already dialed in (ETTR or otherwise), it allows very quick changes to DOF while maintaining the same exposure without the need for a reference photo that AutoETTR requires.

[a1ex]

I can see why one would want a faster shutter (to avoid motion blur), but in APEX this is measured in seconds (Tv = time value), so this is more of a maximum shutter (or, clearer, maximum exposure time?)

For the limit, I find the soft constraint quite nice (it adjusts some other parameter, then if you really insist, it breaks the limit).

What I'm missing (but I'm not sure how to implement) is to make sure it always follows the same path (for example, if you turn one wheel back and forth the same number of clicks, you should probably end up in the same position). But this again requires inverting the order that you chose from menu...

[Audionut]

I should learn to get some sleep before attempting to be legible 

Soft constraint is nice.  Do you think you could map it to safety shift?  Canon 5D3 menu, C.Fn1:Exposure.  Or allow the user to choose the safety shift in ML would be a better idea, for those bodies that don't have this Canon feature.

How about using lowest ISO as priority?  We may not end up back where we started, but if we don't, at least we are at a lower ISO.  A check for constraint violation could be worthwhile.  If constraint has been broken, attempt to fix it first.

[Audionut]

What about linking a shutter value to WARNINGS_FOR_BAD_SETTINGS?

Where is "WFBS" defined in the source?

[Audionut]

what if the lighting situation changes? How do I compensate on the fly then?

This got me thinking.  It would be handy to have a button to override Auto Expo.  You could then disable AE (hold button), re-meter the scene, enable AE (release button).