Monitoring HDR on Graphics Display

Hello Hive! Long time reader and first time poster on the new forum!

The studio has recently installed the Ezio ColorEdge CG319X for our HDR projects. I was curious if the Graphics display on linux is suppsed to be also configured for HDR as well, or is setting the Flame Graphics Color Space and Physical Monitor settings all that is needed?

I guess my main concern is about the Graphics Display’s luminnance to match that of my HDR broadcast monitor I’d need to have the PQ/HLG clipping set to 300cd/m2, any content over 300nits then becomes clipped. When the PQ/HLG clipping is set to 1000cd/m2 nothing gets clipped however the brightness no longer matches my Broadcast Monitor and content is pretty dim, not sure the nit levels. I’d assume i’d want this clipping function ‘off’, but if its off the monitor becomes very dim!


Welcome @tylerf . Glad you are here. This sounds like something @finnjaeger or @val might know.

Thanks Randy, I’ve also been enjoying all of the podcasts and Logik Lives!

1 Like

Hi, Tyler!

There is two problems in what you try to achive.
First is that your monitor (according to manufacturers spec) has max brightness 350 cd/m2. So it can oly clip all signals that go beyond this setting (and try to emulate HDR), or sqeeze everything you through in it to not clip, and it becomes dim, like some kind of log signal.

Second part of a problem is more complex. As far as I know nowadays there is no way to reliably monitor HDR content on GUI monitor. Problem relies in ability of operation system to control brightness on part of a screen, not whole. If I not mistaken only Apple MacOS + XDR display combo can do such a thing, and it still in experemental state. Imaging you have a displaying device that can do 1000 cd/m2, without this ability Flame (or any other software) GUI in HDR would become a mess - imaging all bright overlay interface parts (like Gmask shape, or Color Warper color circles) becomes a laser ray that shine in your face, and you dont want it. I hope I describe it clearly.

So in conclusion - use your broadcast monitor to monitor HDR correctly and set your GUI monitor to something SDR-ish with some tonemapping.

Hope this helps


As someone who predominantly works in HDR, you don’t want to be looking at it on a HDR GUI. For 2 main reasons really.

First of all, none of the HDR GUI displays actually do HDR very well. As mentioned previously the luminance peaks are way too low. You’d be better off spending a similar amount on a domestic OLED and calibrating that to check your work on (feeding it out of your SDI or potentially HDMI tunneling) Most of those are still only 600-800 nits but you would generally only clip specular highlights above those sort of nits anyway. Lining up a calibrated LG C8 against our X300, you can see a slight difference in the highlights but not one that you would pick if you had to walk between rooms.

Secondly, I personally would not want to be looking at a HDR display up close for a full day of work. You could adjust all the different GUI display settings for each app potentially so anything “white” doesn’t burn out your retinas or cause annoying dimming. I.e. change the background and text colours.

Hope that helps.

1 Like

Thanks for the feedback guys. That’s sort of what I figured with the UI… I was hoping that Linux or Autodesk would have implimented an adjustable GUI that was sort of turn into HDI mode where the white peaks would just get clipped but the images stayed correct. Maybe in the future it will get implimented.

The Monitor however is great. The quality and size was is great. I would have issues with the previous monitor where I would loose a ton of detail trying to do cleanup work even with the Aces SDR transform

1 Like

I agree with everything that has been said, sdr on gui and hdr on reference display works great for me, I just shift+E on gui if I want to see details
in the shadow/highlights .One of the greatest benefits of flames colormanagement!

I also agree that the aces-SDR transforms arent the best. I preffer the arri one personally, I have made a custom one based on the arri709 for OCIO but I havent yet ported it to flame, its based on CDLs and color matrixes so Its possible I recon. (you can easily implement it as a 3D lut but you cant invert it which I like to
do for graphics) .

I also agree that the apple EDR stuff is great and I hope something like this comes to flame - Its certainly possible even in Linux. Even if not through KDE/XORG it should still be possible to send a full PQ gui to the monitor, with a customizeable graphics NITs for the gui monitor. The OS would still be looking crazy but maybe thats ok… clipping setting would in that case be on the monitor.

I dont have a HDR computer display to test, But IIRC even changing the graphics setting in colormanagement does change the gui as well, or? I cant remeber …maybe that was macos only

I tried the EDR stuff in nuke on mac and it really is awesome to comp in HDR, even if its relative and not absolute like PQ it makes a big difference in how much you see.