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Using Magic Lantern => General Help Q&A => Topic started by: emphram on December 18, 2014, 02:59:56 AM

Title: Limited auto iso or some sort of semi automatic functions? [600D]...
Post by: emphram on December 18, 2014, 02:59:56 AM
Hey folks, I do wedding and other social events videography, and have been using magic lantern for a time, but I notice that some times there isn't enough time to set things manually without missing the first few vital seconds of an action, for instance, from the bright exterior of the church to the dark interior, I have to change the aperture but also the ISO, I kinda wish iso was automatic (maybe even aperture) but limited to only a certain level (max iso 1600). Is this possible some how? Auto iso in the interior of the church flies up to 3200 when 1600 is fine, due to the weird lighting conditions of the church.

Suggestions?
Title: Re: Limited auto iso or some sort of semi automatic functions? [600D]...
Post by: walter_schulz on December 18, 2014, 07:44:22 AM
Activate module AUTOEXPO.mo (included in nightly builds) and discover P-mode on steroids.
http://www.magiclantern.fm/forum/index.php?topic=7208.0
And take a look at Expo. Lock in Expo tab.
Title: Re: Limited auto iso or some sort of semi automatic functions? [600D]...
Post by: dmilligan on December 18, 2014, 01:08:43 PM
Quote from: emphram on December 18, 2014, 02:59:56 AM
Auto iso in the interior of the church flies up to 3200 when 1600 is fine
I'm going to assume you're talking about video. It's not completely clear from your post. I'm also going to assume you're talking about regular H.264 video and not raw video.

If ISO 3200 is not clipping highlights (use zebras to see this), then it is better to use that than 1600. It will be less noisy (assuming all other exposure parameters are the same). On the 600D, ISO 3200 is a "digital" and not "analog" ISO, so with raw data, it's not particularly useful (it's simply a digital manipulation that could be done in post, noise levels are the same), but it will be marginally better with H.264, because H.264 doesn't encode the full 14-bit range of raw data.

See also: http://www.magiclantern.fm/forum/index.php?topic=5693.0
Title: Re: Limited auto iso or some sort of semi automatic functions? [600D]...
Post by: emphram on December 25, 2014, 11:14:41 PM
Yes that is the problem, the camera goes to iso 3200 and I get clipped highlights, ISO 1600 is nicely exposed and less noisy, it would be good if we had program function for video or a way for limiting autoexposure parameters in videomode.