Latest post Sun, Oct 26 2014 10:16 AM by othila. 10 replies.
Page 1 of 1 (11 items)
Sort Posts: Previous Next
  • Wed, Feb 5 2014 10:34 PM

    • Marc_89
    • Not Ranked
    • Joined on Thu, Aug 4 2011
    • Posts 130
    • Points 1,750

    All exports have gamma shift MC 7.0.3

    Hey there,

     

    whenever I export my timeline to whatever codec, it is always darker and mostly with much more contrast than what I see in my record monitor.

    I edit on a iMac 2013 on Mountain Lion 10.8.5 with Media Composer 7.0.3

    I remember in the past, old Computer with 10.6.8 and Media Composer 5.5 when I exported to for example Prores422 HQ it looked exactly like in my record monitor, wich was great.

    I edited Canon 5D MkIII footage with the All/i codec so I started a YCbCr project and transcoded my footage to DNxHD.

    But when I export to Prores 422 it has a gamma shift and everything is much darker. It doesnt matter if I export from Media Composer or use Quicktime reference with Sorenson Squeeze or Mpeg Streamclip.

    Strangely, when I export to DNxHD mov everything is more pale and less contrasty.

    I m very confusd now... how do I get a nice small export like a h264 out of my timeline without it making my video so much darker? 

    *Media Composer Academic 8.2.0* on a Mac with OSX 10.9.5.* iMac late 2013 Intel Core i7 quad 3,5Ghz, 24Gb RAM, Nvidia GTX780M, Thunderbolt, USB 3.0 [view my complete system specs]
  • Wed, Feb 5 2014 11:13 PM In reply to

    Re: All exports have gamma shift MC 7.0.3

    Transcode or mixdown to ProRes or DNxHD, then export Same As Source. If you use Custom settings you are using the horrible QT engine to encode. 

    Also: when watching ProRes in QT player, that does convert Rec709 legal levels to linear computer screen levels. 

    After a Same As Source, use Squeeze (which you got with MC) or another encoder of your choosing to convert to H264 or whatever you desire.

    Media Composer Symphony | PT Ultimate | Win10 HPZ | OSX MBP | ISIS5000 [view my complete system specs]
  • Wed, Feb 5 2014 11:25 PM In reply to

    • Marc_89
    • Not Ranked
    • Joined on Thu, Aug 4 2011
    • Posts 130
    • Points 1,750

    Re: All exports have gamma shift MC 7.0.3

    Hello Job ter Burg, thank you for the advice.

    I did as you said and mixdowned to Prores 422 HQ MXF. The mixdown looked exactly as my source material in the source or record monitor, as expected.

    Then I exported same as source as you said and still I got the same problem...

     

    Another thought:When I export same as source in DNxHD, or transcode any Canon5D.mov to DNxHD codec, my videos have always brighter blacks than what avid shows me in my record monitor. Maybe avid shows me my DNxHD transcoded material in the wrong way? I tried "expand luminance for computer displays" for full screen mode but no change.

     

    I uploaded two pictures to show my export process:

    http://abload.de/image.php?img=bildschirmfoto2014-02gvjbz.png

    http://abload.de/image.php?img=bildschirmfoto2014-023ks74.png

     

    Another test:

    In the picture below I imported a DNxHD 185 video file into avid. The source file is on the right. After I imported it into avid the blacks changed. When I export it "same as source" to dnxhd.mov it again looks the same as the source material on the left. So avid shows me a darker picture I think...

    http://abload.de/image.php?img=bildschirmfoto2014-0296o8j.png

    All I need is to be able o export my clip the way I see it in avid... so either avid shows me wrong blacks or the mistake is somewhere else... and in addition, when I export to Prores422 or h264 I always get even more much much darker blacks...

     

    *Media Composer Academic 8.2.0* on a Mac with OSX 10.9.5.* iMac late 2013 Intel Core i7 quad 3,5Ghz, 24Gb RAM, Nvidia GTX780M, Thunderbolt, USB 3.0 [view my complete system specs]
  • Thu, Feb 6 2014 9:12 AM In reply to

    Re: All exports have gamma shift MC 7.0.3

    Don't judge color and luminance in the Source/Record monitors. And if you use Full Screen Playback, make sure to set the luma level correction for that monitor.

    Avid works in Rec601 or Rec709, which are video color spaces. Computer monitors work in a different color space, with different luma levels. A luma level of 16 in video is full black, where it is a near-black grey on a computer monitor.

    As for levels changing during import/export, you might want to read up on the settings here: http://www.jobterburg.nl/Publications/601_709_RGB.pdf

    Media Composer Symphony | PT Ultimate | Win10 HPZ | OSX MBP | ISIS5000 [view my complete system specs]
  • Sat, Feb 8 2014 8:21 PM In reply to

    • Marc_89
    • Not Ranked
    • Joined on Thu, Aug 4 2011
    • Posts 130
    • Points 1,750

    Re: All exports have gamma shift MC 7.0.3

    Thank you Job ter Burg for those instructive words.

    As I am editing right now for playback on other consumer computer monitors and casual HDTVs, I just wanted the final result to look exactly as I saw it last - in the record monitor. 

    I found a strange workaround with exporting the timeline to prores 4444 and alpha filter 16-235... I can then re-compress it to a smaller codec like h264 for sharing and the colors and black look the same. When I export from the dnxhd to h264 directly, no matter what compression application (sorenson, qt7 pro, adobe compressor, mpeg streamclip) I always get bad results, may it be much more "washed out" or simply so dark you can barely see.

    I think this works for me for now...

    Thank you again for your education.

    *Media Composer Academic 8.2.0* on a Mac with OSX 10.9.5.* iMac late 2013 Intel Core i7 quad 3,5Ghz, 24Gb RAM, Nvidia GTX780M, Thunderbolt, USB 3.0 [view my complete system specs]
  • Tue, Feb 25 2014 3:38 PM In reply to

    • darkoibr
    • Not Ranked
    • Joined on Wed, Mar 30 2011
    • Posts 127
    • Points 1,700

    Re: All exports have gamma shift MC 7.0.3

    I was just gonna say... The workaround I found was to export to pro res 4444 with no gamma correction.. Comes out the same as I see it in record window.. However on my work station when I export same as source it comes as just as it should.. I am confused about it..

  • Wed, Oct 22 2014 4:20 PM In reply to

    • Dave
    • Not Ranked
    • Joined on Wed, Oct 22 2014
    • Los Angeles
    • Posts 1
    • Points 15

    Re: All exports have gamma shift MC 7.0.3

    I know this is a long dead thread, but I'm having the exact same issue and unfortunately, exporting to ProRes 444 with no gamma correction does not solve the problem for me. Maybe things have changed since 2011 when this workaround still worked? 

    To reiterate the issue, I would like to make an h.264 quicktime that matches the gamma of what I'm seeing in the Avid Record monitor (the one on the computer GUI monitor). I know that this is not an accurate representation of what it would look like on a proper video monitor in 601/709 color space, but since the piece is intended for web viewing, I would like the final piece to match what I'm seeing on my computer monitor.

    I am on MC 8.0, cutting on DNxHD 36 (this is a roughcut before finishing with higher quality), exporting a same as source and then making the h.264 in Compressor. To be clear, the Same as Source file matches what I'm seeing in the record monitor. When I make the h.264 however, the blacks get crushed and I lose crucial detail in the dark sections. 

    Is there any other known workaround or simply a fix to get an h.264 to match the gamma/full swing color space of the original same as source?

     

    2.8ghz 2014 Retina MacBook Pro

    OS X 10.9.5

    MC 8.0

    Compressor 4.1.3

    mid 2014 Retina Macbook Pro 2.8 GHz Intel Core i7 16 GB Ram OS X 10.9.5 Media Composer 8.0 Compressor 4.1.3 [view my complete system specs]
  • Sun, Oct 26 2014 3:21 AM In reply to

    • hbrock
    • Top 25 Contributor
    • Joined on Thu, Oct 13 2005
    • Bainbridge Island, WA
    • Posts 5,560
    • Points 64,815
    • Moderator: Avid Xpress Pro Mac
      Moderator: MCA Mac
      Moderator: Media Composer Getting Started

    Re: All exports have gamma shift MC 7.0.3

    Most projects are set up using 601/709 video levels (black = 16 and white =235) while computers expect full range RGB levels where black = 0 and white = 255.  Avid doesn't re-map video levels to computer levels in the Composer or Source montior on your computer, so while the levels are correct when displayed on a video device (i.e. television monitor) they will be slightly washed out on your computer screen.  First thing: check the format tab in your project and see whether you're using 601/709 or RGB levels.  For a DNx36 project it should be set to 601/709.  Next, use the waveform monitor in the Color Corrector to confirm that your black levels are around 16 rather than 0.

    Just to make things more "interesting", Apple will re-map ProRes QuickTimes to display blacks at 0 and whites at 255 on a computer display regardless of whether the levels are set for RGB or 601/709.  This happens in both QuickTime player and in Final Cut Pro. Unfortunately if you send out something with RGB levels when 601/709 are expected you might well get your "correct" levels re-corrected resulting in crushed blacks and blown out whites.

    Make sure you export using the 601/709 levels rather than RGB.  You should see the correct levels when using Compressor to make your h.264 file.  The gamma may shift slightly due the conversion from one codec to another but it shouldn't be noticable unless comparing both files side by side.

    MacPro, MacBook Pro and a Cube (masquerading as a kleenex dispenser). [view my complete system specs]

    Must think of something clever to go here...

  • Sun, Oct 26 2014 6:01 AM In reply to

    • othila
    • Not Ranked
    • Joined on Thu, Sep 29 2011
    • Posts 206
    • Points 2,550

    Re: All exports have gamma shift MC 7.0.3

    Hi Job,

     

    I'm not seeing the gamma problems in MC 8.1 but I could be wrong.

     

    This is what I'm doing in 8.1

    AMA footage

    Transcode to DNXHD 185

    Export to ProRes HQ 422

     

    I don't see any gamma issues.

     

    My old work flow was.

    AMA footage

    Transcode to DNXHD 185

    Mixdown

    Export QT reference

    Import QT reference into Apple Compressor

    Add a Apple Prores 422 HQ template and switch the "Output colour space to preserve".

     

    But with MC 8.1 I'm straight to ProRes HQ 422

     

    Do you have any findings on this with 8.1?

     

     

    Cheers

    Avid Media Composer 8.3.1 Matrox MX02 on MacPro4,1 Quad-Core Intel Xeon 2.66 GHz, Memory: 16 GB, OS 10.8.5, NVIDIA Quadro 4000 [view my complete system specs]
  • Sun, Oct 26 2014 8:22 AM In reply to

    Re: All exports have gamma shift MC 7.0.3

    Haven't used 8.x (I need ScriptSync).

    Thing is: I doubt the MC version would make a difference, because as soon as you do a Custom QT export, it's not MC that is doing the encoding, it's QT. And QT is the culprit. Also: it'll be considerably slower at exporting, since QT is old 32-bit code, whereas transcodes inside MC (and in modern applications like Squeeze) are 64bit and may therefore use more CPU cores.

    Media Composer Symphony | PT Ultimate | Win10 HPZ | OSX MBP | ISIS5000 [view my complete system specs]
  • Sun, Oct 26 2014 10:16 AM In reply to

    • othila
    • Not Ranked
    • Joined on Thu, Sep 29 2011
    • Posts 206
    • Points 2,550

    Re: All exports have gamma shift MC 7.0.3

    Hi Job,

    Is there anyway of checking that a straight export to Prores is rendering a correct gamma?

    Cheers

    Avid Media Composer 8.3.1 Matrox MX02 on MacPro4,1 Quad-Core Intel Xeon 2.66 GHz, Memory: 16 GB, OS 10.8.5, NVIDIA Quadro 4000 [view my complete system specs]
Page 1 of 1 (11 items)

© Copyright 2011 Avid Technology, Inc.  Terms of Use |  Privacy Policy |  Site Map |  Find a Reseller