Re: [Avid-L2] What Should be Legal Range and What should be Full Range in an HDR workflow?

Here's another factor I have to deal with.  I'm running an Aja Hi 5 to go SDI te HDMI and trigger the C9 LG OLED into HDR mode.  Feeding YCbCr or YUV there is no level control for input or output.  If I feed it 4:4:4 then I can adjust both input and output level.  I confirmed from the shop that did my LG and PVM calibration that it was done with the test generator in legal level mode.  The assumption by the Aja Hi 5 is that anything YUV is legal level but even when I send it YUV out of Resolve I can switch between Data(Full Range) or Video(Legal Range) and it effects the monitor output level.  So for me running in video levels for monitoring should work for dual output.  It's the video essence of the final file that I want to confirm should be Full Range or can it be Legal Range and properly flagged?

Another what I believe to be new wrinkle is that it seems with a recent software update on my LG OLED C9 the calibrated settings of Cinema (User) which are available in HDR mode in the preset choices are no longer available when I stream Dolby Vision content.  I'm pretty sure it use to offer the Cinema (User) choice when streaming but now it's not there.  I see the usual presets of standard, game, Cinema (Home), Cinema etc... but not the calibrated one.  I checked with the facility that did the calibration and they said this means now they have to do three calibrations on LGs.  One for SDR, one for HDR and now one for Dolby Vision.  After googling around I did find information that said YUV was supposed to be Legal Range but clearly it can be made at either level.

So if I run in legal range with the dual output of HDR and SDR I would think the Dolby Vision Trim pass would still be valid.  I think this is why the target display for 100 nits says it's full range so like everything else in Resolve is process Full range after the input and before the output this makes the Target Display stay matched to the HDR side of the dual output.  As you pointed out it's all about scaling in the end.  So if I did all this monitoring legal then when I go to the delivery page and tell it to be Data(Full Range) I would think that would be right.

I do have media info and I see in your example the Color Primaries are BT.2020  and the Transfer Characteristics are PQ.  Are Transfer Characteristics the same as the Electro-Optical Transfer Function?  I know HDR is done in PQ but where in this media info screen does it specify if this file is Legal or Full Range?  I'm not versed in what the Matrix coefficients that are BT.2020 non-consistant means.  Most deliveries for Dolby Vision I've heard about are constrained to P3-DCI space some are P3 in s Rec 2020 container.  Are the previously mention media info specs what the "container" is flagged as.

I find it confusing how to follow everything through the pipeline like I grew up in linear edit bays because the final encoders etc... seem to have a protocol/mind of their own that often doesn't really analyze the actual signal level in the video essence but looks at metadata flags that clearly can often be incorrect for the actual video essence.  Why can't someone make a 3/4inch to 1inch HDR bay for me???  ;-)

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