Magic Lantern Forum

Using Magic Lantern => Raw Video => Topic started by: jaybirch on July 07, 2013, 09:24:15 PM

Title: Raw and Highlight Tone Priority
Post by: jaybirch on July 07, 2013, 09:24:15 PM
I know we are supposed to switch this off, to get better speed... But i can shoot 1080p continuous with this on, for thought I would run a few tests with it.

I shot this exposed for the highlights, then tried the same with HTP on. I certainly helps bring the shadows up, without too much noise. As you can see on the bottom two grades.... Bringing the shadows up further shows the HTP disabled has more noise.

The highlights with HTP on seem to have blown a bit, which makes the whole thing a bit pointless, but perhaps with a bit more testing i can find a nice middle ground.

(http://s16.postimg.org/s3n320t11/DNGM07_1935_000000.png) (http://postimg.org/image/3zwbdqak1/full/)
Title: Re: Raw and Highlight Tone Priority
Post by: a1ex on July 08, 2013, 01:50:12 PM
Can you post the raw files?
Title: Re: Raw and Highlight Tone Priority
Post by: dariSSight on July 08, 2013, 02:32:36 PM
Quote from: jaybirch on July 07, 2013, 09:24:15 PM
I know we are supposed to switch this off, to get better speed... But i can shoot 1080p continuous with this on, for thought I would run a few tests with it.

I shot this exposed for the highlights, then tried the same with HTP on. I certainly helps bring the shadows up, without too much noise. As you can see on the bottom two grades.... Bringing the shadows up further shows the HTP disabled has more noise.

The highlights with HTP on seem to have blown a bit, which makes the whole thing a bit pointless, but perhaps with a bit more testing i can find a nice middle ground.

(http://s16.postimg.org/s3n320t11/DNGM07_1935_000000.png) (http://postimg.org/image/3zwbdqak1/full/)

I think the RAW photo with the HighlightTonePriority Off is the best one, if you decide to add some contrast or brightness it won't over expose the buildings and the bush area. I'm not sure what's a Wide DR but the Graded shot leaves to much over exposure for me, then again the human I see a little over exposure.
Title: Re: Raw and Highlight Tone Priority
Post by: Audionut on July 08, 2013, 03:23:15 PM
In photo mode, HTP has the same limitations as digital ISO's.
Title: Re: Raw and Highlight Tone Priority
Post by: 1% on July 08, 2013, 04:13:16 PM
What about HTP + ettr?
Title: Re: Raw and Highlight Tone Priority
Post by: jaybirch on July 08, 2013, 05:19:08 PM
Quote from: a1ex on July 08, 2013, 01:50:12 PM
Can you post the raw files?

Here you go...

http://stylecreative.net/uploads/HTP.zip

Thanks, Jay
Title: Re: Raw and Highlight Tone Priority
Post by: IliasG on July 08, 2013, 05:56:31 PM
Strange !!!

The effect is the exact inverse from what we know about HTP in photo-raws. Are you sure you named correctly then ON/OFF ??.

Can you write the camera settings you used ?
Title: Re: Raw and Highlight Tone Priority
Post by: jaybirch on July 08, 2013, 06:03:27 PM
I was thinking the same.... I was using BATCHelor for the first time, so maybe it does things differently in terms of name/date.

I'll redo the test again with a clipboard shortly.
Title: Re: Raw and Highlight Tone Priority
Post by: a1ex on July 08, 2013, 06:14:14 PM
As expected, this comparison simply tells the obvious: ISO 200 has cleaner shadows than ISO 100, but 1 less stop of highlight detail.

ISO 200 HTP is nonlinear digital gain applied to ISO 100. To compare them in raw, try ISO 100 without HTP and ISO 200 with HTP. These two use the same analog amplification.

In my tests I did not notice any difference between these two.
Title: Re: Raw and Highlight Tone Priority
Post by: mageye on July 08, 2013, 06:14:27 PM
This may be be of interest:

http://forums.planet5d.com/threads/86999-Sticky-Highlight-Tone-Priority-ISO-Noise-Tests (http://forums.planet5d.com/threads/86999-Sticky-Highlight-Tone-Priority-ISO-Noise-Tests)

(apart from the fact that ISO 160,320,640 etc. are now NOT considered best for RAW video. Is it right that now ISO 100,200,400 etc. are considered to contain less noise?)
(That's what I have been using ???)
Title: Re: Raw and Highlight Tone Priority
Post by: a1ex on July 08, 2013, 06:19:06 PM
160, 200 and 250 are 100% identical in raw. And probably 400 HTP too.
Title: Re: Raw and Highlight Tone Priority
Post by: jaybirch on July 08, 2013, 08:57:14 PM
The more i read about it, the more useless it sounds, in Raw. So i will discontinue the HTP testing, for now.

If you guys want me to test anything though, just shout. I'm amazed what you guys have done with ML, truly amazed and thankful.
Title: Re: Raw and Highlight Tone Priority
Post by: ch_d on October 04, 2013, 01:47:35 PM
any news about HTP?
Title: Re: Raw and Highlight Tone Priority
Post by: a1ex on October 04, 2013, 01:49:00 PM
What news? it's digital gain, no effect on raw.
Title: Re: Raw and Highlight Tone Priority
Post by: ch_d on October 04, 2013, 01:51:26 PM
alright, thanks.