Working with HLG footage

[Paul Anderegg]

OK, so an update. I bought a brand new 2018 Sony X900F HLG capable 4K HDR TV set, so that I could see my HLG footage in original unmolested unconverted HLG glory...or so I thought. Every HLG exported timeline, be it FCPX or Resolve, with all settings retaining all HLG with no alterations, resulted in pathetic inaccurate video files, that looked like raw slog. I gave up on that, and thought, hey, just plug the camera directly into the TV and see what HLG looks like...yeah, didn't work. Brand new Sony HLG camera and brand new HLG TV...the TV does NOT recognize the HMDI output of the PXW-Z90 as an HLG/HDR signal, and as such, it looks horrid. I can though manually switch the TV into HLG mode for the input, which I did, but all this did was increase the backlight to maximum, and the image was still a washed out colorless log looking grainy disappointment. Switching the TV to HDR10 mode even looked better, but still did not look as you would expect. The TV was set to enhanced mode, the camera was set to HDMI 2160/1080p output.

So my final thoughts on Sony "instant HDR" workflow...well, there is still nothing instant about it, and the ONLY workflow I can make usable is to AQUIRE in HLG, and DELIVER in HDR10. If you know about HLG, then this would seem backwards, as you are not supposed to shoot in HLG, as HLG is supposed to be a delivery format. If I had a way to grade in HDR, I would play around with Slog3, but I don't know the first thing about grading slog, even in SDR. All HDR10 material starts life as slog type footage or film...RAW too, so not sure what Sony was going for with this "instant HDR" marketing ploy.

See the below link "if you plug in said camera to a 4K TV with HLG HDR support, it will immediately play it back with the appropriate contrast and tones, including the brighter highlights and increased contrast that make HDR so appealing. This ability is also what makes this an “instant” HDR workflow"

https://www.bhphotovideo.com/explora...2855/KBID/3801

Paul

[Cary Knoop]

What are your settings in Resolve, both your color managed settings and the output codec.

[Paul Anderegg]

Color managed by Resolve, all three selectors to HLG 2100, luminance output turned on.

Paul

[Cary Knoop]

Originally Posted by Paul Anderegg

Color managed by Resolve, all three selectors to HLG 2100, luminance output turned on.

If you destination is HLG you should not tone-map.

What codec did you use?

[Paul Anderegg]

Oh crap, maybe thats why it looks better when viewed in HDR10 mode. I need to buy a cheap HDR/HDMI output device so I can see what is happening prior to several hours worth of encoding a file just to see the results.

Typically use ProRes, so that I can Handbrake it into 10 bit HEVC.

Paul

[Cary Knoop]

Originally Posted by Paul Anderegg

Oh crap, maybe thats why it looks better when viewed in HDR10 mode. I need to buy a cheap HDR/HDMI output device so I can see what is happening prior to several hours worth of encoding a file just to see the results.

Typically use ProRes, so that I can Handbrake it into 10 bit HEVC.

I personally find x264 using high10 or high422 in an mkv container easier all you need to do is to re-encode your encoded mov file with this:

ffmpeg -i file.mov -c:v libx264 -profile:v high422 -crf 14 -color_primaries bt2020 -colorspace bt2020_ncl -color_trc arib-std-b67 file.mkv

[Paul Anderegg]

Im trying to find the easiest way to view my darn files on my TV, which has limitations on what codecs it supports. Trying another Resolve export with tone mapping set to off, then a quick conversion to 10 bit h264 in HandBrake to see the results.

Paul

[Cary Knoop]

Originally Posted by Paul Anderegg

Im trying to find the easiest way to view my darn files on my TV, which has limitations on what codecs it supports. Trying another Resolve export with tone mapping set to off, then a quick conversion to 10 bit h264 in HandBrake to see the results.

But I would make sure the metadata is added as well: -color_primaries bt2020 -colorspace bt2020_ncl -color_trc arib-std-b67

[Paul Anderegg]

Speaking of metadata, here is what FCPX says when you attempt to export an HLG project. I think the term "not ready for primetime" applies here. :-|

I also attempted an HLG ARIB STD-B67 export out of Resolve, tone mapping off, and it came out extremely dark.

Paul

[Cary Knoop]

Originally Posted by Paul Anderegg

I also attempted an HLG ARIB STD-B67 export out of Resolve, tone mapping off, and it came out extremely dark.

Assuming you exposed it properly it should be just right for a monitor or TV that is HLG compatible.

How are you watching this?

Are you trying to upload an HLG video or are you trying to convert a HLG video to Rec.709?

[Paul Anderegg]

Footage was exposed using the Z90 built in EVF/LCD gamma adjust settings. I am watching these files plugged into the USB jack of my Sony 4K TV. There is no other means to view HLG for me other than HEVC through the USB, or ChromeCast Ultra after uploading to YouTube.

As for exposure, these HLG files, when converted to HDR10 (PQ) in FCPX, looked perfectly fine and have normal shadows and midtones, with extended bright colorful highlights up to 1000 nit. Nothing I have attempted so far in passthrough HLG looks right. I would say it ends up looking the same on the HLG TV as it does on my SDR computer monitors, washed out and grainy.

I found out how to properly export REC709 from HLG BT2020 in FCPX...you must set the files to REC2020 colorspace override in the settings info menu...the rest of the project/timeline is left as REC709. Doesn't look quite as good as native REC709, but close enough you would have to know the camera to really tell.

Paul

[Cary Knoop]

Can you show me a screen grab of the RGB parade?

[Paul Anderegg]

This is HLG2100 timeline, ignore the previous ARIB reference in the export window. I don't know how to read these values, I am used to IRE and NIT from FCPX.

Paul

[Paul Anderegg]

Same clip scope view in FCPX.

[Paul Anderegg]

And FCPX when conformed to PQ using standard HDR tools effect.