Here is an animated comparison of just the Dim surround
This is effectively acts as a kind of comparison of SDR and HDR images.
The grey is a familiar SDR target value ( Y =0.10ish) and the Diffuse white Value is a common target for HDR output (Y=100)
Even though this is only an “ideal” color appearance transform, from one viewing condition to another and not necessarily a tasteful render from linear to display, it should still be worth considering because these basic transforms (or their precursors) have probably been used in the optimization or evaluation of every imaging system (Film, Television, Printing Industry) since the 1960’s.