Magic Lantern Forum

Using Magic Lantern => Raw Video => Topic started by: mannfilm on July 29, 2013, 07:33:04 PM

Title: How do you use ETTR while shooting RAW video
Post by: mannfilm on July 29, 2013, 07:33:04 PM
Sorry, but I cannot understand how to use the ETTR with video. Not sure if anything is happening when I follow the still photo steps. Can someone explain the steps to me for using ETTR with RAW video? Thanks in advance.
Title: Re: How do you use ETTR while shooting RAW video
Post by: mannfilm on July 30, 2013, 12:36:46 AM
Answer - you don't use ETTR with video.  ETTR adjusts both shutter and iso. It will change your "video" shutter speed (1/60) to something else. Use zebras instead.
Title: Re: How do you use ETTR while shooting RAW video
Post by: Midphase on July 30, 2013, 09:02:36 AM
Well, you do want to use ETTR with raw video, but you want to do it manually.

Essentially you want to make sure you enable raw histograms in your global draw, then as you're framing your shot you want to tweak your ISO and aperture to get you as close as possible to maximum exposure (e.v. 0), you don't want to go into - but you also don't want to be too far into the + either.

Your best bet is to experiment and then check your resulting files in Resolve or whatever you use for post processing, after a while you'll get the hang of it.
Title: Re: How do you use ETTR while shooting RAW video
Post by: Yuppa on July 30, 2013, 06:32:43 PM
Do you mean don't use "Always ON" for video?

This is misleading as there any MANY options for ETTR.  You can certainly set the trigger mode to the SET button and use it that way when you're composing your scene.  Underexpose manually (on purpose) a tad, press the SET button, let ETTR do its "thing" then press record.  If you get a "Whoops," adjust the exposure manually.  Easy.
Title: Re: How do you use ETTR while shooting RAW video
Post by: Andy600 on July 30, 2013, 06:38:07 PM
Don't use the auto ETTR module for raw video as it will alter shutter speed.

Manually expose to the right using the raw histogram.
Title: Re: How do you use ETTR while shooting RAW video
Post by: Midphase on July 30, 2013, 07:11:13 PM
What Andy just said (which is what I said, but apparently Andy can say it better than me).
Title: Re: How do you use ETTR while shooting RAW video
Post by: Andy600 on July 30, 2013, 07:34:33 PM
LOL  ;D I think the confusion was between ETTR as a method and ETTR the module
Title: Re: How do you use ETTR while shooting RAW video
Post by: tronics on July 30, 2013, 10:09:15 PM
I think the problem is how to use expose to the right ETTR.

So you need a histogram for that and this you get with global draw on.
However there is an option to hide all this stuff as soon as hitting record.
So you do not have the performance drain of global draw but make your exposure correctly before you start

Cheers
Title: Re: How do you use ETTR while shooting RAW video
Post by: gtsofilms on August 23, 2013, 06:43:28 AM
Sorry, might have missed this somewhere, but what is the option to hide the histogram and the global draw info after everything's set and right before you're ready to shoot!

And many thanks for the clarification about ETTR in video mode!
Title: Re: How do you use ETTR while shooting RAW video
Post by: arrinkiiii on August 23, 2013, 02:47:49 PM
Quote from: gtsofilms on August 23, 2013, 06:43:28 AM
Sorry, might have missed this somewhere, but what is the option to hide the histogram and the global draw info after everything's set and right before you're ready to shoot!

And many thanks for the clarification about ETTR in video mode!

In the 7D i don't need to go to ML menu to disable the histogram... just press Info button.
Title: Re: How do you use ETTR while shooting RAW video
Post by: simulacro on August 23, 2013, 02:55:27 PM
(https://lh4.googleusercontent.com/-ruaGJ3egvLs/UhdbTr32TxI/AAAAAAAACLY/dLFQT8xsq08/s800/2013-08-23%252014.48.23.jpg)

on the 50d: powersave in liveview

sorry for the crappy pic
Title: Re: How do you use ETTR while shooting RAW video
Post by: johansugarev on August 23, 2013, 04:53:03 PM
The way I expose is - fps override on - 24fps, exposure override on - 1/48 preferably; Basicly any fps has double the shutter speed. Then I put a variable ND on the lens and watch the raw histogram. Just like in audio - you want it to cover at least halfway the histogram and strive to get it as much to the right as you can without going over the right border - clipping. Simple.
Title: Re: How do you use ETTR while shooting RAW video
Post by: gtsofilms on August 24, 2013, 12:39:32 AM
Interesting! Thanks for the power saving suggestion.  johnansugarev- would you mind explaining the rationale behind adding the variable ND filter? Does that help so it doesn't look too bright? You take it off before shooting?

I was wondering if there was a way to have global draw on and off with a shortcut key, I noticed with the info button I can toggle to the Canon info which shows shutter speed/aperture/exposure/iso but even having that info up on the screen seems to slow write speed a little bit.  With Global Draw function off, I can toggle the info button until there are no displays on the screen aside from the framing window.