Hi Omar, I think you have this figured out but here are my thoughts on your approach.
-
If I remember correctly Eizo CG319X has 2 options (or maybe you can create 2 options with color navigator) for PQ viewing. One will tone map the source down to 300 nits - so you wont see much clipping but it wont be accurate PQ either. The other is accurate to about 300 nits and then clips. On the pattern you downloaded check the grayscale to see where it is clipping.
-
I recommend that you use the ODT Rec2020 ST2084 (1000 nits P3 limited) for grading since the display cannot accurately show beyond P3 and that is what most services ask for in the small print
-
As you have found you cannot use the GUI for this you need a BMD decklink card - since you can switch the eizo to HDR modes you do not need HDMI 2.0 support, but it is nice to have in case you want to attach it to a TV with brighter capabilities. Using a video card bypasses the OS color management and puts your resolve project in control which is essential for grading decisions
-
As Nick points out the IDT for the HDR test pattern you are using should match the ODT when testing dynamic range. If you select rec 709 as the IDT, then the expected behaviour is that the pattern would look just like it does in rec 709 even if your ODT is set to 2020 PQ. In other words your CMS is saying please display this rec 709 source “correctly” in 2020 PQ. The idea of that pattern is to fill the 2020/ 10000 nit bucket and see how much of it the display can show, and how it deals with the code values it cannot show - matching the IDT and the ODT does that because the ramp goes from code value 0 to 1023. To see if your display is setup correctly try “Spaces” in Downloads — Finalcolor or use the original ACES supplied targets Dropbox - ODT - Simplify your life
Good luck!