Re: [Avid-L2] Quicklimes with wrong levels flags.

I know that in some cases it doesn't scale the video level.  Way back when I had to deliver XDCam 50 files and it was when Adobe Media Encoder would accept QT reference files.  I would export a QT Ref from Avid.  I found AME would export incorrect level XDCam50 files if I left the checkbox set to legal or back then I think they called Rec 709 in the checkbox.  If I set the check box to old name RGB/Full Range in today's term then the XDCam 50 would export correctly.  Given I was sending AME a QT reference the video essence from the Avid timeline was all legal level regardless of which checkbox I selected on Avid export.  It was AME that must have seen the flag or something change and interpreted it differently.  IIRC when exported as legal/Rec709 the AME export was low but when exported from Avid at Full Range/RGB the AME export was proper legal level.  I only figured out the pattern of behavior by trial and error.

Over the years I've been told from the Avid Camp that if I link to a file then check in source settings that there are no color adapters or scalers it should output the true video essence level of that file but again I've had times especially when using some Avid native codecs that when linking back into Avid it really seemed like there were some under the hood flags being read and interpreted.

On the Arri sight their LUT maker a few years back assumed all the camera material was legal level and that was the only choice you could choose on the production side of the LUT builder.  I assumed from that the the files from Arri Log C were supposed to be legal level and their LogC to Rec 709 LUT worked well in my experience as did the one Avid came up with IIRC.  It seems most other Cameras/Codecs create their log video essence in Full Range.  It seems weird because the Log signal never even reaches legal level in actual value is way inside legal level on scopes so it always amused me as to what was legal vs full range in the log world.  How Avid handles level scaling on the input side to LUTs has also been confusing and hard to pin down.  I remember back in the 8.4/8.5 Avid days different versions of Avid would input scale LUTs differently.  I experienced that on Panasonic Varicam 35 using the Panny Vlog to Rec 709 LUT.  I don't know why there isn't some visible way to see these aspects of under the hood level scaling before and after LUTs or color adapters.

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