Latest post Wed, Sep 12 2012 2:40 PM by Job ter Burg. 17 replies.
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  • Sat, Mar 24 2012 5:14 PM

    • jledy
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    DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Hey All,

    I've been banging my head against the wall trying to make this work and i'm coming up with nothing so I thought i'd call in the big guns and ask for some help.

    I'm post-supervising a short film that recently got into a film festival that has asked for a quicktime for exhibition. They want it to be Apple ProRes 422 (HQ) in Rec 709. Our final, color-corrected media is Avid DNxHD 175 X, graded to be 709 legal.

    I exported from our sequence by Sending to QT with the following specs: Codec: ProRes 422 HQ, gamma correction off, chroma filtering off, color levels 601/709, native dimensions (1080p).

    I checked my SMPTE color bars and this export squeezed all my levels together so that my super black was at 28 and my white was at 218. I'm guessing this was some kind of strange correction that wanted to take my values outside of 709 and put them into it, thereby squeezing the whole film into less color space that 709.

    I retried this export, now setting the export color levels to RGB. Now my color bars are clipped at 16, but all values above 16 are for the most part accurate (I noticed some 1 point shifts in some channels for each bar which I'm assuming has to do with rounding occuring in the transcode). Overall, this is an improvement from the previous export because the film doesn't have any values below 16 and therefore the levels for the film overall are accurate--however, part of this delivery is to include 30 seconds of SMPTE bars and I don't want to send inaccurate color bars for a projectionist to calibrate to.

    I then tried exporting at 4444 in Rec 709 space, and this produced the closest version of the color bars--my super black is 0, my black is 16, my white is 235. There are some minor shifts in channels like the 422 hq version, but otherwise levels are good, however I still can't figure out a way to compress that down to 422 HQ without losing that super black information.

    SO, any thoughts?

    Thanks,

    Jordan

  • Sat, Mar 24 2012 5:33 PM In reply to

    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Not going to work like that, sorry, because of the combination of Quicktime conversion and the ProRes codec.

    The only way I found this to work:

    - in MC6-Mac (only works on Mac), do a video mixdown of your 175x sequence to ProRes HQ. A mixdown, not an export. This way, your mixdown will be Pro Res inside an MXF Mediafiles container.

    - Do a same-as-source export of this mixdown.

     

    This will ensure that all color levels are maintained, in my experience.

    MC6 is mandatory, as that is the first version to natively support ProRes. Mac is also mandatory, since Apple won't allow PC's to encode Pro Res.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sun, Mar 25 2012 4:47 PM In reply to

    • jledy
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Thanks Job!

    That seemed to resolve the issue, great advice.

    I did notice that when I export same as source, the audio channels are encoded as Big Endian instead of Little, which isn't a huge deal. I was able to re-export from Quicktime and convert the audio to little endian without altering my color bars, although it did make the file twice as large. I'll probably give them the Big Endian version anyway since all my research seems to say it makes almost no difference whatsoever.


    Thanks again!

    -Jordan

  • Sun, Mar 25 2012 5:21 PM In reply to

    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    You could also export video-only, then marry sound and picture in QT Pro again? Never got to understand the ins and outs of big/little endian.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Tue, Aug 21 2012 10:47 PM In reply to

    • Editosaurus
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Do you know why it is that a Prores HQ mixdown is so huge? It's 4x the size of an DNxHD175.

    I was going to try the workflow of mixing down to Prores HQ and then exporting same as source but I cant afford the 450gbs it's going to take to do that. Any ideas?

    2014 MacPro, 6 Core 3.5GHz Intel Xeon E5, 64Gb RAM. Dual AMD FirePro D700 Graphics. OSX 10.10.3 Avid MC 7.0.4.3 [view my complete system specs]
  • Wed, Aug 22 2012 6:58 AM In reply to

    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Are you by any chance in an RGB709 project, mixing down to ProRes 4:4:4?

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Tue, Aug 28 2012 12:08 AM In reply to

    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    How would you accomplish this in mc 5.5? I think i am about to have the exact same issue. 

    Brendan

  • Tue, Aug 28 2012 10:15 AM In reply to

    • Mikee Carpinter
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    i found in mc 5.5 the best work flow to keep color is

    1, do a video mix down

    2, export same as source

    3 create pro res hq file through quiktime pro 7

     

    all levels will be the same

    Mac Pro 2008 Two 2.8GHz Quad-Core Intel Xeon processors AVID MC 5.5 Davinci Resolve 8.2 Nvidia Quadro 4000 GPU NVidia 8800 Display Black Magic... [view my complete system specs]
  • Tue, Sep 11 2012 11:14 AM In reply to

    • Editosaurus
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Hi Job ter Burg.

    Thanks for all your help with this. I really appreciate it. I've tried all sorts of things to avoid having to delete things on my hard drive to make space for this big Prores MXF mixdown. But it looks as though I can't avoid it. I even tried to transcode to DNxHD175x and export a quicktime using same as source. Unfortunately this gives the exact same blocking.

    So do you have any idea why the Prores MXF is so big? At the moment a Video mix down is going to cost me 500gb, when the final prores output will be about 125gb. I've checked any haven't ticked 444 anywhere and I'm not in RGB709. The project is 80mins long.

    Can I do a video and audio mixdown, or do I have to do the marrying up somewhere else? I can't get Quicktime Pro 7 working on my computer so I would have to marry it in FCP, and the irony seems a little too much.

    Again, thanks for your help

    James

     

    2014 MacPro, 6 Core 3.5GHz Intel Xeon E5, 64Gb RAM. Dual AMD FirePro D700 Graphics. OSX 10.10.3 Avid MC 7.0.4.3 [view my complete system specs]
  • Tue, Sep 11 2012 12:48 PM In reply to

    • Editosaurus
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Okay, so it turns out that the massive anticipated file size for Prores MXF is actually false. It estimated 480gbs and the final output was 125gb, which is what I had thought it should be.

    Very happy. Though, again, disappointed in Avid's perpetual bugginess and general inaccuracy in any sort of exporting (the most important part film making - actually having a finished product.)

    2014 MacPro, 6 Core 3.5GHz Intel Xeon E5, 64Gb RAM. Dual AMD FirePro D700 Graphics. OSX 10.10.3 Avid MC 7.0.4.3 [view my complete system specs]
  • Tue, Sep 11 2012 12:55 PM In reply to

    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Mikee Carpinter:

    i found in mc 5.5 the best work flow to keep color is

    1, do a video mix down

    2, export same as source

    3 create pro res hq file through quiktime pro 7

     

    all levels will be the same

    Not when I tested it.

    The only proper way I found is Transcode or Mixdown to ProRes INSIDE MC, then export Same-As-Source.

     

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Tue, Sep 11 2012 6:49 PM In reply to

    • Mikee Carpinter
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Hi Job

    How do you mix down to pro res in avid 5.5 I though this was not posssible until version 6?

    Mac Pro 2008 Two 2.8GHz Quad-Core Intel Xeon processors AVID MC 5.5 Davinci Resolve 8.2 Nvidia Quadro 4000 GPU NVidia 8800 Display Black Magic... [view my complete system specs]
  • Tue, Sep 11 2012 7:01 PM In reply to

    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Sorry, v6 only.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Tue, Sep 11 2012 7:02 PM In reply to

    • Editosaurus
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Okay, just followed that...

    Don't do a mixdown. That creates the same blocking. The only way it works is to transcode the sequence and then do Same as Source.

    2014 MacPro, 6 Core 3.5GHz Intel Xeon E5, 64Gb RAM. Dual AMD FirePro D700 Graphics. OSX 10.10.3 Avid MC 7.0.4.3 [view my complete system specs]
  • Wed, Sep 12 2012 7:56 AM In reply to

    • Editosaurus
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    • Joined on Sat, Feb 11 2012
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    Re: DNxHD 175x to Apple ProRes 422 HQ - HELP!

    Okay,

    So now I've transcoded half my sequence as a test. I can now export a clean image using same-as-source to Prores. However, I have titles: PNGs with an alpha layer in the transcoded sequence, and whenever I Export anything Same-as-source that includes this I get blocking and playback issues. Do I have to put the titles on in a different program? Or is there a way of setting the render files to Prores MXF (in fact, I imagine if this is possible then this would solve the problem altogether).

    Any suggestions would be appreciated.

    James

     

    2014 MacPro, 6 Core 3.5GHz Intel Xeon E5, 64Gb RAM. Dual AMD FirePro D700 Graphics. OSX 10.10.3 Avid MC 7.0.4.3 [view my complete system specs]
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