Fri Jul 21, 2023 11:32 am
The HDR color-bar standard, ITU BT.2111, is available. A Google search will find it for you.
Having worked in transmission for many years, I can tell you that standardized color bars are still quite useful.
The upper strip of the color-bar signal is 100%; the remainder is 75%.
Below are some sample 10-bit values taken from TABLE 2 of the spec (R-G-B):
100% White: 940-940-940
75% White: 721-721-721
100% Yellow: 940-940-64
75% Yellow: 721-721-64
0% Black: 64-64-64
-2% Black: 48-48-48
+2% Black: 80-80-80
+4% Black: 99-99-99
For setting monitor brightness make the +2% and +4% bars "just visible".