Exposure preview in M mode isn’t sticking when focusing - why?

[bcapphoto]

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Question - when I’m shooting with the SL2-S, manual exposure, when I half press the shutter to focus, the expose seems to jump into an auto mode and it wipes out my manual expose setting (goes too bright or dark). It’s even worse with AF-C. Why?

[bcapphoto]

If it helps, with more detail ...

1. I set the exposure mode to manual, so I set aperture, SS and ISO.
2. I underexpose the scene on purpose, which I can preview in the EVF/LCD.
3. As soon as I half-press the shutter button, the exposure jumps to a "normal" exposure. Note that if my Exposure Compensation is +/- that preview when I half-press seems to represent that exposure compensation value.

The image itself is exposed properly the way I intended during #2. But if I am constantly focusing (i.e. AF-C) and need to adjust shutter speed as I am going (which happens often), then I cannot preview the effects.

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[Luke_Miller]

Try setting P-A-S-M  to P-A-S.

[Photoworks]

On 7/2/2022 at 4:49 PM, bcapphoto said:

Question - when I’m shooting with the SL2-S, manual exposure, when I half press the shutter to focus, the expose seems to jump into an auto mode and it wipes out my manual expose setting (goes too bright or dark). It’s even worse with AF-C. Why?

are you using a flash?

[bcapphoto]

21 hours ago, Luke_Miller said:

Try setting P-A-S-M  to P-A-S.

That shows me the preview while I'm NOT focusing. But as soon as I half-press the shutter, the manual exposure preview goes away and it jumps into "auto" mode. 

[bcapphoto]

8 minutes ago, Photoworks said:

are you using a flash?

Nope, no flash. 

[bcapphoto]

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A few examples of how/why you'd shoot this way. I thought this was fairly standard? 

 

#1 - I'm photographing a bride walk down the aisle. I've set the exposure manually because she's backlit by the doors. As she walks towards me, the light from the front of the church is brighter. I'd want to transition to a faster shutter speed (while tracking her and photographing her). With Leica, I cannot see the effects of that shutter speed change while focusing.

 

#2 - I'm photographing a lifestyle family session and I have them positioned up against a really bright coloured wall. I've set the exposure manually. I'm using AF-C because they're moving around and I want to keep shooting fluidly, but as soon as I half-press the shutter, the auto mode takes over and shows me them underexposed.

 

These are very normal and average shooting scenarios that I easily encounter at EVERy session. So this would get in the way EVERY session. 

Edited July 5, 2022 by bcapphoto

[Photoworks]

all I can think is that the AF needs a particular light condition to work best. is it is too dark or too light at you focus point the contrast AF will not work well

I never use AFc so I have never seen this problem, I use AFs and keep refreshing the focus...

This is something you may want to ask Leica and maybe it is something they can address.

[Luke_Miller]

My SL bodies are set up for back button focusing, so I am in manual focus and the rubber joystick activates autofocus when depressed.  With my settings nothing happens with a half press of the shutter. The only time I have an issue with exposure preview is in the studio with my studio flashes where I have to disable exposure preview in order to compose and focus. My guess is you can find a set of settings that corrects your problem.

[Luke_Miller]

Follow up.  Normally I am in AF-S.  If I am in Manual Exposure and significantly underexposed I will get a brief flash in the EVF when I initiate autofocus.  Apparently the camera wants more light while trying to achieve focus.  If I go to one of the AF-C modes the EVF will stay bright during the autofocus process.  Autofocus performance with Contrast Detect systems depends on sufficient light hitting the sensor, so this appears to be normal for the camera.  Since I am normally in A or S exposure mode I had not noticed this before.

[Luke_Miller]

Follow up 2.  The reason I never saw this issue previously is that in the same situations listed by the OP I am in Aperture Priority and use exposure compensation to compensate for backlighting or bright backgrounds.  Even with significant underexposure compensation dialed in I do not get the EVF brightening.

 

My guess (and it is only a guess) is that in full manual exposure the EVF displays the actual exposure as seen by the sensor.  So brightening may be needed to achieve autofocus. In A-S-P exposure mode the EVF displays a simulated view of the effect of the exposure settings while the sensor actually receives the light it needs for autofocus. The exposure settings are only applied during exposure.  That would explain what I am seeing.  But I could be wrong and often am. Just ask my wife 😀.

Edited July 5, 2022 by Luke_Miller