Participating Frequently

Question

REC709 and sRGB - no color management difference

Forum|Forum|12 years ago
May 20, 2013
2 replies
46575 views

We know, there is only a gamma difference (to make it simple) between REC709 and sRGB and this gamma difference is quite important for serious work.

I never used color management in AE in the past, because it slowed down the fps for the preview.

Yesterday I wanted to check how it works in CS6 and I found out this:

There is no difference between REC709 and sRGB in color management in After Effects CS6 Win or Mac?

I set the color management on and choose REC709.

I import a footage (I tried every possible format - stills, video, video seq... with or without embeded profiles).

In interpret footage box - if I choose something weird like Film or cieRGB or widegammutRGB, I see the change in the viewer.

But if I am switching between sRGB and REC709, I see no difference.

I see the message, that the gamma will be corrected from 1.9 to 2.2, but it is not happening.

Well... I used the similar concept in Nuke and Smoke and it works there, just I don't know what I am doing wrong in AE ?

And yes, I read all the help files and tutorials 10000x.

Thank you for any ideas in advance.

Milan

This topic has been closed for replies.

P

paulinventome

Known Participant

AFAIK there is a difference between REC709 and sRGB curves, they're not just gamma curves, i can't remember off the top of my head but the shadows flatten out into a linear line with one of them. Whether the difference is enough for you to worry about depends on what you're doing. You can see the LUTs in Nuke on the project settings and compare the curves.

There should be a difference applying a REC709 vs sRGB profile on injest. Are you in 32 bit float project mode? Your viewing LUT/profile is set to sRGB? What is the footage and format you're importing? Is there something in that footage that is overriding your selection?

You can also not apply a profile on injest and apply one via an effect afterwards, perhaps try that to see if you can see it working

Sometimes AE attempts to be a little too clever and automatic, whereas Nuke tends to leave it up to you and not 'auto decide' anything.

hth

paul

M

Milan_MichalikAuthor

Participating Frequently

Hi, finally someone who is with me :-) and I see that you asks good questions :-)

I know that there is more difference then the gamma (this is why I wrote: make it simple) in my first topic.

"Is there something in that footage that is overriding your selection?"

Right question. This is what I am asking too. But I've tried all codecs and all formats, even stills, with embeded and non-embeded profiles. What should I test more?

"Are you in 32 bit float project mode?"

I tried 8bits, 16bits and 32float too.

"Your viewing LUT/profile is set to sRGB?"

Just right now my windows monitor is set to sRGB, my After Effects color management is set to sRGB. And my footage is REC709. So I see it's too dark in sRGB color space, I see less resolution in blacks and my picture is darker.

I opened AE and Nuke on the same time, same computer, same monitor, same footage.

I set sRGB for Nuke and AE as a color space. Viewing color space is sRGB on both.

Read node in NUKE: colorspace sRGB = picture is darker, colorspace REC709 = picture is correct.

Import interpret footage AE: colorspace sRGB = picture is darker, colorspace REC709 = picture is darker, no change

THERE iS EVEN MORE !

If I set simulate output view to REC709 instead of sRGB, my AE composition stills the same.

If I do the same in NUKE, it changes of course.

I see I have to build a LUT and use this workflow in AE, just I wonder that I am alone in the world who cares about this problem???

I am not an NUKE artist or employee, who wants to promote NUKE, or other application. I own After Effects and I want to use it in a right way.

5 minutes ago I tried the same on Mac = same problem Win/Mac = so it isn't my computer fault.

So the question is: Is there anybody who sees a difference in the picture when you injest (import) a footage in 2 different ways, first as a sRGB and then as a REC709???

Mylenium

Legend

I use full range REC709 and no plugins... let's wait for your workstation or for other volunteer to check it :-)

The feline hit it on the head - in an environment that uses any form of Gamma correction, the differences would be minor or non-existent. All Adobe apps obey the operating system's default Gamma and based on their interpretation rules and the hardwired stuff in the file format plug-ins also the Gamma values as defined by the format spec, then the color engine does its magic, adding a further level of control with color profiles where necessary.

Mylenium

Legend

Well, but do you actually use color management onb your system, i.e. a monitor profile?

Mylenium

M

Milan_MichalikAuthor

Participating Frequently

Yes, I do. I use sRGB monitor profile - because my monitor is not REC709, but sRGB. Just I do not understand, why you are asking this question :-)

Again, on the same system, in NUKE, when I set my project as sRGB and when I switch my input footage to REC709 instead of sRGB, I see the difference in gamma.

When I do the same in AE, I don't see the difference. REC709 or sRGB - the same.

Mylenium

Legend

Well, working with color profiles makes no sense on an unmanaged system, that's why. Do you actually assign the profile for comp preview/ use it in Nuke? As far as I'm concerned, I see nothing wrong here. Seems more to me like you are working unmanaged in Nuke and are misinterpreting it's lack of Gamma compensation for how things should look in AE...

Mylenium

Sign up

To post, reply, or follow discussions, please sign in with your Adobe ID.

Sign in to Adobe Community

To post, reply, or follow discussions, please sign in with your Adobe ID.

Scanning file for viruses.

This file cannot be downloaded