To wrap this up the QC house did some research and found that Clipster was mis interpreting the file as Full Range at the start of the ingest. If they set it to legal range at the point everything looks correct to them. They said they had seen this type of error before but didn't really have the specifics as to why it happens.
Bottom line is the file is okay and it was how Clipster interpreted the video essence level that was incorrect. Not the outstanding question is why did it misinterpret it. Perhaps there is something in the fact that I had a DNxHR HQX sequence that I rendered the upper track to ProResHQ to make it a ProResHQ QT Ref file. Could there be any residual metadata/flags coming from the DNxHR HQX media that somehow filtered into the equation that makes clipster mis read the video levels of the file.
---In Avid-L2@yahoogroups.com, <jeff@...> wrote :
------------------
Jeff Hedberg
Union Editorial
575 Broadway,6th floor
New York, NY 10012
On Apr 17, 2018, at 1:40 PM, bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:QC lists some elevated black as +50mV IN Head and +5mV IN Full. That would be the exact opposite of what I see. I agree and so has Avid tech engineers in the past that linking to a file as long as no scalers is applied in the source setting is an accurate representation of the video essence of the file.
I wonder of the nomenclature of Head, I assume short for headroom, and Full is indicative of a particular type of QC hardware? Clearly they can view the file with scaling or not it just seems like their system is misinterpreting things out of the gate so to speak. Reminds me of how some embedded LUTs from Arri will add a legal to full range scaler before hitting the Arri embedded LUT.
If there is some sort of metadata flag in the file for a .mov it sure would be nice to be able to view it.
---In Avid-L2@yahoogroups.com, <cutandcover@...> wrote :Extreme Reach is the same. For whatever reason, even though my ProRes outputs from MC are perfectly legal, created as Same As Source from Video Mixdowns, Extreme Reach QC will reject for levels. Some QC can't see it for some reason. I gave up trying to convince them. All of my Extreme Reach deliveries from that point are DNxHD 709.I don't know how you could alter or see the metadata that QuickTime reads to display as full range. I do know that I've never doubted the accuracy of linking the file and looking at the live video output from either MC or Premiere through I/O, checking the scopes.If you know you are right, but someone else "knows" you are wrong, there is often no convincing them, even though you are actually right.On Tue, Apr 17, 2018 at 1:03 PM, John Moore bigfish@... [Avid-L2] <Avid-L2@yahoogroups.com> wrote:My workflow for 4K QC is to render my upper track safe color limit to ProResHQ and do the same with submasters over filler. This creates a QT Ref export that is ProResHQ and I check legal levels on the QT ref export settings in Avid. My source media is DNxHR HQX. When I open the QT Ref in QT Pro 7 it shows ProResHQ as the codec. I do a save as and everything is fine on my end. If I link back to the resulting self contained .mov it is proper level on my external scope and matches the timeline and Avid sees it as ProResHQ. There are no source setting vid level scalers being applied as I've checked. This tells me the video essence in this file is legal level. I can also take the file into Black Magic Media Express and it is proper Rec 709 Legal level.QC is saying my file is full range but I know it isn't. Clearly something on their end is either interpreting the file incorrectly or their is an improper flag in the meta data of the file. We are waiting to hear back from QC for clarification. I've had them flag this before and a few years back another facility said something similar about an HD file I made using the same basic workflow.So how can one access the Full Range vs. Legal metadata flag in a .mov? I have media info but don't recall such a parameter listed. I know the video essence is legal level based on all my tests and the fact that it was a QT ref out of avid with the legal level box checked.What is the most accurate and thorough way to check a .mov metadata related to legal vs. full range?John Moore Barking Trout Productions Studio City, CA bigfish@...
Posted by: bigfish@pacbell.net
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