Latest post Sun, Mar 28 2021 2:47 PM by Jason Sedmak. 40 replies.
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  • Sun, Jun 14 2020 5:18 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Jason Sedmak:

    Are you exporting exactly the same thing you rendered out of Resolve? e.g., if your Resolve renders are 4k, but your export out of AVID is HD, then sometimes (depending on a few factors) this export can cause a color-shift if you don't mixdown first. That's because if there's a conversion required for the export, AVID would historically use QT-Conversion which is known for causing color-shifts. Mixing down first is the cure.

    Yes, both are the same resolution and both are same codec ProRes 422 HQ @ 4K DCI 4096x2160.
    Jason Sedmak:
    If you're trying to base the color accuracy of your final file using any sort of QT Player, don't bother. It NEVER interprets the gamma correctly. The 100% best way to look for a color-shift from your export is to AMA-link your exported QT back into AVID, throw it into the source side, and put your final sequence that you exported on the record side. Place them both on the same frame and activate Gang. Then bounc back and forth between the source and the record watching your outboard monitor signal (not computer UI) to see if there's a shift. Of course, the best way to do this is to be using scopes on that outboard signal, becuase you'd see a shift with ease.

    Unfortunately, I'm not as advanced as you, I'm not fully sure I completely understand what you've said above, but I think you are suggesting I need a monitor for color grading so that I can check the scopes and waveform? Is that right?
    Because I don't have a color grading monitor, I instead loaded both clips into DaVinci Resolve and used the waveform and scopes and could see some minimal differences. Oddly thou, if I import the exported sequence ProRes 422 file from Media Composer into DaVinci Resolve and re-export without any grade added to the clip, the gamma corrects itself.
    Jason Sedmak:
    My facility requires using ProRes so this is the crappy world I'm used to, but the best way to avoid color-shifts is to use DNx in the workflow all the way to the end. ... and I haven't had a chance to suss it all out 'tho, but I recommend comparing your exported QT like I explained above to verify it's good to go (even if QT players say otherwise).

    I can pass along my graded clip and MC export for you to take a look? Both are a few seconds long.

     

    Thanks so much,
    Sean

  • Sun, Jun 14 2020 7:45 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Upon further testing, it appears to be mostly related to the QuickTime gamma issue. Both clips look the same in VLC and in DaVinci so close that I can't really tell the difference visually. Honestly, QT looks different than DaVinci and VLC and it's probably casuing the gamma difference. so idk at this point.

  • Sun, Jun 14 2020 8:34 PM In reply to

    • jef
    • Top 25 Contributor
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    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    It is pretty much accepted that viewing any file in a web browser is a crap shoot. Too many variables and dependencies. 

    I only evaluate a file in a device which has true, accurate waveform and vector scopes.  For example, this would be Resolve or Avid (using Link or Consolidate only, not classic Import unless it is a still).  Premiere is a bit iffy in my experience.

    The best thing to try is make a file  of SMPTE Color Bars from Avid’s provided files.  Export.  Link it back in.  Place it on a track above the source used for the export.  Go to Color Correction.  Get the scopes up.  Compare the two tracks.  They should be virtually identical (depending on the export codec used).

    You can learn a lot this way.

    Good luck,

    Jef

    Avid DS 11.0.2 R.I.P | MC "Well, it depends ..." mostly 8.12.9|OS 10.14.x - iMac Pro 2019 - home system MacPro Dual 2.8 8core GTX680 "Harpertown"... [view my complete system specs]

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    Senior Editor

    Old Stuff  http://vimeo.com/album/3037796

  • Sun, Jun 14 2020 10:38 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Sean,

    im happy to evaluate for you if you wanna send me a snippet of your Resolve render and your Avid export. 

    Custom, i9-9900K, AMD Radeon Vega 64+Radeon VII egpu, 64 GB RAM, m.2 SSD, 8x 10GigE to Terrablock, BM SDI 4k, currently running Mac OS 10.15.7. MC Ultimate... [view my complete system specs]
  • Mon, Jun 15 2020 3:07 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    This issue is related to "Data Levels" inside DaVinci Resolve on deliver tab. When Data Levels "Full" is selected there is differences in the gamma or contrast. Selecting Data Levels "Video" solved the issue and the video exports from DaVinci Resolve and Media Composer always match.

    What's your take? When would one set the Data Levels to "Full" for graded clips?

  • Mon, Jun 15 2020 3:46 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Well, yeah, if you were mistakenly rendering with Full data levels, that would definitely mess up your colors. Video codecs that utilize "video" levels -- such as ProRes 422HQ -- require "video" color levels. Only if you're using "RGB-Full" codecs -- like quad 4 ProRes would you ever set that to Full.

    Avid bases it's color conversion based on the codec. So if it sees a ProRes HQ, e.g., it will assume the file has video (partial) color levels. If this mistake happened at the render and there's no going back, you could put a color-space transformation in the source-settings in AVID to map them back to the correct map, but in this case, I'd definitely recommend you do a video mixdown afterwards.

    J

     

    Custom, i9-9900K, AMD Radeon Vega 64+Radeon VII egpu, 64 GB RAM, m.2 SSD, 8x 10GigE to Terrablock, BM SDI 4k, currently running Mac OS 10.15.7. MC Ultimate... [view my complete system specs]
  • Tue, Jun 16 2020 10:35 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Thanks for all the help you all.

  • Thu, Mar 25 2021 6:13 PM In reply to

    • Shredit
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    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Hi Jef,

    I have a 1 1/2 hour doc starting and I am researching workflow. I notice you mentioned multicam. 

    My goal is to use resolve to sync audio, output proxies. Then cut in Media Composer with lots of FX (saffire and compositing) and mulitcam groups, then output for return trip to resolve for color grading where the colorist in another city who will have a copy of all the master media can relink and do the color, then send me the colored master clips that I can relink in Media Composer, render out FX and deliver final product.

     

    In the past I have always done the proxy workflow in AVID but the relink never works as planned and I always end up with a partial relink and end up overcutting with the masters, doing a DnX 444 hi res output and deliving that to the colorist in Resolve. Then they just color that master and give it back to me.

     

    My question is since I will be doing the multicam groups in AVID will those files come across going back to Resolve?

    Also are you still using Resolve for your proxies and having success?

    I am going to be doing some testing but I was hoping for some insight.

     

    thanks

     

    Troy

  • Sat, Mar 27 2021 2:53 AM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Troy,

    In a linked-file workflow, yes, any multi cams groups will translate for relinking to Resolve, however, it's best to commit the clips before you export the AAF, and once you render out of Resolve, you'll have difficulty relinking back in Avid with the ".sub" group clips if you don't use Resolve's AAF. Last time I did it (without using an AAF) I deleted the ".sub" off of each clip name manually so that I could relink my Avid sequence to the Resolve QT suffix renders.

    There are numerous workflows, of course...rendering mxfs out of Resolve for your Avid MediaFiles folder, rendering QTs, rendering using suffixes, exporting AAFs...it's all up to you and your use case. Now I'm not a fan of exporting an AAF out of Resolve personally, because you now have an entirely new sequence, nor am I a fan of mxfs for relinking, but everything has its purpose.

    Good luck,

    j

     

    Custom, i9-9900K, AMD Radeon Vega 64+Radeon VII egpu, 64 GB RAM, m.2 SSD, 8x 10GigE to Terrablock, BM SDI 4k, currently running Mac OS 10.15.7. MC Ultimate... [view my complete system specs]
  • Sun, Mar 28 2021 10:52 AM In reply to

    • Bruno M
    • Top 150 Contributor
    • Joined on Thu, Feb 11 2010
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    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    In my role as part-time editing lecturer, I'm often having to deal with student problems as a result of alternative/unorthodox workflows they have adopted.

    One that has come up a number of times is issues with creating proxies in Resolve (for use in Avid MC), not relinking to the camera originals once back in Resolve.

    This is down to the fact that if you export OP-Atom MXF proxies from Resolve (which will directly go into the Avid Mediafiles folders) they are missing important metadata. Specifically, the Source File name and path info is not present. If you Link to the same file and transcode within Avid, you'll see this metadata exists, but not in the Resolve proxy.

    This was causing problems with relinking the Avid-generated AAF in Resolve. 

    One way to alleviate this problem was to to create a Reel name/number in Resolve for the clips you want to export. You do this by setting the option (in the General/Conform options) 'Assist using reel names from..' to 'embedded in source clip file'. This assumes the info is there in the camera file, which we found was case with RED rushes.

    Once this option is set, you'll notice all your clips will have reel names/numbers. Once exported, these will appear in Avid under the 'Tape' column. This info will be carried across in the AAF and allow relinking to the original rushes.

    As a further refinement, we also found that exporting an ALE (Avid Log Exchange) file from Resolve and bringing this into Avid (which come in as master clips) we can carry some other metadata over (such as Scene and Take) which might have been recorded by the camera. Unfortunately, creating ALE files didn't solve the Source file name & path problem, so we still had to create the Reel info.

    HP Z800, HP G3 Studio, SonnetFusion RAID, Mojo DX, Decklink 4K, Symphony 2020, JVC DTV1910 HD tube monitor, HP Dreamcolor, Avid Artist Color, Avid Transport... [view my complete system specs]
  • Sun, Mar 28 2021 2:47 PM In reply to

    Re: Avid Media Composer & DaVinci Resolve Round Trip Bug/Defect

    Bruno,

    That's a spectacular write-up and I'm sure will prove helpful for many! 

    No workflow is without its "gotchas," but I've been avoiding the OP atom mxfs in my workflow for years for these (and other) reasons, because I've found the linked file methods to be by-and-large the most resilient-- especially with all the crazy file types/camera files I find myself dealing with. Paramount is avoiding the renaming of Master Clip Names, but the concept worth adding is that as long as one has TWO fields that can be matched (the first and main being timecode) one can relink just about anything no matter the workflow. 

    Custom, i9-9900K, AMD Radeon Vega 64+Radeon VII egpu, 64 GB RAM, m.2 SSD, 8x 10GigE to Terrablock, BM SDI 4k, currently running Mac OS 10.15.7. MC Ultimate... [view my complete system specs]
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