FORUMS: list search recent posts

Confusing problems evaluating video brightness

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Tom Clasman
Confusing problems evaluating video brightness
on Apr 19, 2017 at 1:04:48 pm
Last Edited By Tom Clasman on Apr 19, 2017 at 1:41:09 pm

Got a problem evaluating video colors and brightness right.

My edited video (exported as AVI, MagicYUV codec) plays back in two distinct different brightness shades, depending on settings and playback system. I need to decide which is 'the right' shade, which will look the same on as many playback systems as possible.

I play back the video in VLC.
If I set the VLC 'video output'¨setting to "Automatic", then the video play back in a way which I label as bright.
If I set the VLC 'video output'¨setting to "OpenGL", then the video play back in a way which I label as dark, it's drastically darker. (see examples)

I've always used the OpenGL setting in VLC, because it makes the blacks in a video translate as absolute blacks. If I set VLC video output to "Automatic", then the absolute blacks are no longer absolute black, but rather shown as slightly hazy, like a pale film on top of the black, as if the contrast value is set too low (see examples)

But my partner in this, is using OSX and plays back the video in quicktime. To him the video always shows as the brighter alternative of the two above. There seems to be no way to set his video playback to show darker, like it does to me using "OpenGL" mode in VLC.
While editing the video in AE, the video is shown to me as the 'darker' translation. But when the same video is played back on a different PC/windows using Windows Media Player, the video translates as the brighter alternative described above.
This difference seems to persist regardless of what lossy endformat I render the file as.

I'm aware of the gamma difference between macs and PC, but this doesn't seem to be the problem here.
The video is shot as simple and straight HD MXF format, and edited as such too.

This all becomes a problem to me, I don't know why this difference occurs and what makes it so. And I cannot decide on which video translation I should see as 'valid', so I can treat brightness and color values correct, and feel confident that this is how most users in the world will see it too. The more outside people who tries this and report their experience back to me, the more confused I seem to get.

I could use some help to understand what's going on and how I can orient myself through this to makes things come out right.
Thanks for any tips/ideas/thoughts

I'm on Win8.1 Pro, Nvidia GeForce GT video card, Dell U2711 IPS-screen connected via HDMI and well color calibrated, using sRGB 1998 color space profile.
(the blow pics are all screenshots of video player window, in the two different brightness shades)








Return to posts index

Roei Tzoref
Re: Confusing problems evaluating video brightness
on Apr 19, 2017 at 2:26:30 pm
Last Edited By Roei Tzoref on Apr 19, 2017 at 2:49:25 pm

from what I understand the colors in the editing system look o.k, and only in the player you are not sure, correct?
try this: import the footage back to premiere/ae, does it look o.k? if so - your video is fine and you can't control other people's players, including your own. Vlc will show one thing, QT will show another, Mediaplayer will show something else, youtube will show something depending on your browser and so on...

so if the problem is in playback, you will never be able to match playback with different players, monitors, Os... your only way of knowing you are getting accurate color is to work with a calibrated professional monitor and even then, you will see the accurate result, but others will mostly see something slightly different. if you say your monitor is properly calibrated then what you see in Premiere/Ae is probably what you are supposed to see. if the problem is from within the editing/vfx software that's one thing, but if the problem is from the playback that's something else.

your playback medium is what matters so if you know you are playing it back in some playback system (say in an exhibition), you should test it there if you can and and see how it looks over there and adjust if you can. in digital cinema you produce a DCP so you can, among other things, make sure the colors will be accurately represented in their playback system. here's a nice post about color differences in playback: https://forums.adobe.com/message/8691969#8691969

Roei Tzoref
After Effects Artist & Instructor
♫ Ae Blues Tutorials


Return to posts index

Tom Clasman
Re: Confusing problems evaluating video brightness
on Apr 19, 2017 at 3:27:49 pm

@Roei Tzoref: Yes, you could say that what I see in different players, different computers/operative systems makes me question players makes me doubt what I see in the editor. In the editor, things look like I expect. I no longer feel confident that what I see is what others will see. What I see there is what I'm using to decide what is the right amount of colors and brightness/contrast.

I re-imported the video into AE as you suggested, and it looks the same as it does in the editing project. This equates to what I call the 'darker' rendering above. That's what I want it to look like.

You say different players and playbacks will differ etc. I understand what you're talking about. But what makes me post this question is that I feel I have identified what seems like two distinct playback lightings, which causes a dramatic difference (check moon pic above).
I mentioned that my partner plays this video back in QT and it looks brighter that it does for me. I can reproduce the brightness he gets pretty much exactly, by simply changing my VLC settings from OpenGL to Automatic. This makes me think I am not seeing the results of subtle differences you get through different players or playback systems, monitor calibrations etc, but rather the effects of two distinct different playback/rendering modes.

Assuming I'm more right than wrong about this, I am asking which of these two modes should be use for more predictable playback results overall. And as a secondary question I'm asking what these two modes are, or what the heck I'm seeing here, and how I can understand this.

I don't think my Dell U2711 screen will qualify as 'professional grade' monitor for serious graphic work. But I don't think it will lead me too far astray either.


Return to posts index


Roei Tzoref
Re: Confusing problems evaluating video brightness
on Apr 19, 2017 at 4:43:50 pm

[Tom Clasman] "I re-imported the video into AE as you suggested, and it looks the same as it does in the editing project. This equates to what I call the 'darker' rendering above. That's what I want it to look like."

then that's how it really looks. what most users will see is depended on their monitors and players. open QT and VLC and WM and you will see differences. there is no "right" but the way you see it in your editor. the question still remains: how viewers are going to see your piece? is it via player? or via web? both will show inconsistent results. if you make your video darker to support what you think is the predictable outcome (your friends computer), and another viewer will watch it through a player that see it darker like your computer, then this viewer will see a much too dark version... what I am saying is that there is no predictability measures you can take here because it's something you can't control.

having said that, if you are encoding to an mp4 format, try using HANDBRAKE to export your mp4. I have seen reports that it produces more satisfying results in color and contrast. https://handbrake.fr/

Roei Tzoref
After Effects Artist & Instructor
♫ Ae Blues Tutorials


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]