Color profile question - HLG color profiles

Hi, I don't know if you ever resolved your issue, and I haven't read the other replies here before typing this (because I stumbled upon this while looking for something else, and believe I can help you).

First of all, let's just state that HLG video (such as what we capture on our Mavic 3 Cine drones) would require a proper HDR display in order to see the full colourspace within our image. If you're viewing it on an SDR display (which is most likely the case, sadly) you will lose much of the colourspace information on your preview window.

For this reason, I have an HDR reference display (calibrated) that I use for much of my HLG processing work (indeed, the higher-end MacBook Pro models such as the M1 Max or M2 models, and even the iPad Pro M1 and M2 models provide a full HDR display with a "Reference Mode" in the Display Options to do claibrated grading and editing work).

If you're stuck with the SDR display, what you can do is apply a Colour Space Conversion from HLG (Rec.2100 HLG) to Rec.709 (SDR). This would perform a tone mapping based on whatever conversion you choose... but, this solution is also less than ideal unless you subsequently render out your video in the limited Rec.709 (SDR) colour space. It would show you an accurate expectation of your export, but only if you're exporting in SDR as well.

Your best option, honestly, if you want to work with HDR and actually OUTPUT HDR is to invest in an HDR display. There is simply no way to get 1:1 replication of the HDR colour space on an SDR display.
The following whitepaper expresses the solutions employed by the broadcast television industry for this exact problem: chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BT.2446-2019-PDF-E.pdf

TL;DR - Close Approximation is the best they can achieve (though their method is extremely scientific and minimizes distingusishable differences when converting between HDR and SDR interchangably, something they need to do all the time in that industry).

If, however, you don't REQUIRE an HDR final render... you can STILL shoot in HLG, and perform a colour space conversion to SDR (Rec.709) and you will STILL benefit from the additional colour space information in your source footage (because you'll have vastly more option and control when it comes to tonemapping to SDR).

I'm a bit of a color management wonk. And really, have to be as I do professionlly teach pro colorists who need to work in Premiere how to do so. So there are some things and concepts I'm very comfortable with that many users aren't, simply because I spend so much time with colorists.

So I could get into say the issues with the Apple choice to apply an odd gamma to Rec.709 video or this or that ... but realistically, let's keep this practical. I'll only give one really technical reply ...

If you're working in HDR, in HLG or PQ, set the preferences for "graphics white" to 203. That is the correct setting for nearly all HDR work whether HLG, PQ, or DolbyVision. You're running 100, which isn't advised. Ok, enough tech geek. Back to the practical stuff.

First ... unless you've got a highly calibrated system using a BlackMagic or AJA breakout device to a highly calibrated pro level reference monitor, well ... color management is pretty iffy. If not a total mess.

Second, what your camera screen shows, or what any video player shows on most systems, is NOT at all necessarily even close to the actual pixel data. Not even a Red or Arri costing $70G and up have a calibrated screen. If it's crucial, pro shoots have heavily calibrated external monitors setup and even then, they mostly trust the false color or zebras for exposure/contrast things.

And third, for those watching after you publish to either say YouTube or Vimeo, their systems, screens, and viewing environments will change the image a lot more than the difference between your example images. Someone watching YouTube on their phone at noon on a sunny day in a park will see a very different image than on that same phone at night in a dark bedroom.

Pcs and Macs will see a very different image due to several things I'm not going into. Vimeo & YouTube ain't the same. Nor are browsers nor video players.

That's Reality 101. Which sucks, really.

Premiere actually has a better probability of showing a closer-to-accurate view of the actual signal data than any video player. Because it's built to work within professional standards, without juicing the image. And most players and even monitors and TVs are designed to "enhance the viewing experience". Meaning they juice saturation and contrast, typically. But it isn't an accurate view of the pixels.

Yea, it's that much of a mess. And to give you an even better jolt, you've never, ever in your life seen exactly what the pro colorist did who graded any media you've ever seen. Whether in a movie theater or big-screen TV or on your computer's monitor. Ain't possible.

Because every screen is different, and even if you connect identical monitors to the same computer, it can be difficult to match one exactly to the other.

So pro colorists are taught right off the bat that 1) you have no control of what anyone sees after it leaves your system 2) no one will ever see exactly what you see while grading and 3) the only way to work is to set up as close to the standards, and let the work go out into the wild.

And get on with Life.

Yea, you can try and out-guess the 'market' for a job, but in general ... that's a waste of your time.

When doing your color work, learn to trust the scopes far more than your eyes! Waveform YC no Chroma is great for showing tonal distribution and contrast. RGB Parade shows the balance between colors top to bottom across the image. Set your blacks, whites, and middle tones by the scales!

The Vectorscope is the saturation scope. And you can check if say your reds are actually red, not yellowish red. Where your skin tones are. And ... how much saturation you have in the least and most saturated colors in your scene. Plus ... the center of the Vectorscope is neutral, blacks/grays/whites, and it that isn't centered, you've got a color cast going on. No matter what your monitor shows.

If you have a good tonal distribution in the Waveform and RGB Parade, your neutral tones are properly centered in the Vectorscope, and nothing is too low or to much satuaration, that image will look pretty normal on any screen ... for that screen. (It's always relative for every screen as to what is 'normal' on that screen.)

I doubt you have the setup that pro colorists have ... I can't even afford the full-on gear they typically run! ... so the best way you can work is produce something, and get it off your system, watch it on something else.

Say upload to both Vimeo and YouTube, as they process color & tonality differently from each other. Then if you're on a Mac, go watch that on both services on a couple PCs. If you're on a PC, watch it on a Mac. Then stream it on a smart TV.

And between them, you'll get an idea of the range of things people will see. And I think it's a lot wider range than you might realize.

Neil