50d - confused by control wheels behavior

[itias]

I'm returning to magiclantern after couple of months and I must say I'm slightly confused by wheels behavior (or rather their influence on movie recording parameters). First of all, the main difference between the version I used to use and current nightly is lack of colors for indicating good values of aperture and shutter values. But bigger issue is the difference in controlling aperture and shutter, or better, my lack of understanding current configuration of ML
So in the past, in M mode, by turning one wheel I was able to change aperture while the other one controlled the shutter speed and display indicated I'm going outside "safe" values by going from green to red for shutter speed. Now with the most recent nightly, one wheel modifies f-value but the other... does nothing, or to be strict, does not change what it displays on the back display (shutter stays at 1/32), but top LCD shows shutter speed changes. Also, ISO changes in response to changing light conditions while for the version I used to use in the past it stays as originally set. I'm puzzled
Can someone be so kind and explain that to me?

Thanks,
Greg

[halbmoki]

Try turning on exposure override in the ML options (expo menu). You probably had it set in the past but forgot about it.
Video mode does auto-exposure by default, but manual exposure is possible with this setting. Note that you can't set longer shutter speeds than 1/30s when filming with 30fps. That's basic math and can't be changed, because more than 30 exposures of 1/30s each just don't fit in one second. You can use FPS override  (movie menu) if you need lower framerates and corresponding slower shutter speeds.

[itias]

Thanks, yes, looks like Expo override does the trick and I'm able to set faster shutter speeds eg. 1/60s, but side effect is that all exposure settings stay the same throughout the entire capture and do not react to changing light conditions like in the default auto-exposure. Maybe there's another setting in the menu, going back to my research.

[halbmoki]

Well, that's what exposure override does - keeping alle exposure parameters the same, even in video mode. I guess, you want a fixed shutter/aperture while the ISO changes automatically during the recording, but currently there's either full auto or full manual mode. On my 50D, I couldn't find a way to enable auto-ISO when expo. override is active, neither with v2.3 nor the nightly builds.

The auto iso module could probably do what you want, as far as I understand, but it's far from being implemented into the ML trunk and currently there's only a version for the 5D3, as far as I know.

[itias]

Thanks, halbmoki! Just to make sure I understand you correctly, currently there is no way (at least for 50d) to have shutter speed in auto mode (h.264) different than 1/32?

And, from my observation it's even crazier in MLV RAW recording. In M mode, live view display always show ISO100 even if exposure pane is set differently. When recording, settings do not change even if exposure override is disabled. But in Av mode, it works more less as with h.264 recording, with shutter set to 1/32. Do you also see the same behavior? Is it worth reporting as a bug, what do you think?

[a1ex]

Canon's exposure implementation in LiveView (aka ExpSim) can't be considered a ML bug

Example: you might have set 1/25 ISO 1600 f/4 (either in M mode or via auto exposure), and Canon code might choose 1/50 ISO 400 f/1.4, which is just as bright. All OK for what the 50D was designed to be - a photo camera.

Since the 50D does not have manual video exposure controls, you have to use Expo Override to get them. But this feature only allows manual exposure (no auto-anything).

With RAW/MLV, ISO only works in full stops, unlike H.264.

[itias]

Thanks a1ex! So you said what I was actually afraid of - looks like there are only 2 options for 50d users:

• full auto mode (Expo Override off), which only gives me control over aperture and Canon adjusts ISO and shutter reacting to light conditions
• Expo Override enabled, which gives me full control and manual exposure, however unlike the option above, Canon does not change anything automatically