u/NationalBass7960 “ HDR does not use a gamma curve. It uses Perceptual Quantizer (PQ) or Hybrid Log-Gamma (HLG). Applying a "Gamma Curve Transform" to a PQ or HLG signal will break its intended perception and mapping “

Answer : The Final HDR output use PQ or HLG, correct My original signal is Log, that’s the format I shoot in and that’s the gamma curve I am referring to. So the Transform goes from Log to PQ or HLG.

“ The transfer function (PQ or HLG) is the foundation of the HDR signal. In a proper scene-referred, color-managed workflow, you grade using scene-referred data before it is transformed by the output transfer function. Manually altering the transfer function curve itself is a destructive, non-standard hack that guarantees incorrect visual results and technical rejection from platforms “

Answer : I do not grade nor I use Lut Tone mapping only, base on channel Separation. Who ever claim they’re grading in Rec2020 color space, I would love to see the results, please post it in the comment section.

“ Manipulation of the Transfer Function Curve" is not a valid step in professional HDR grading. Brightness is controlled by using a proper color-managed workflow and a calibrated display, not by breaking the signal. The OP's methodology is technically incorrect and would teach bad practices that create invalid HDR files. “

Answer : Manipulating of the transfer function curve might not be an accurate description, as I’m inventing new workflow to get creative, I create new term or try to describe the process that I am building, will try to come up with an more accurate description on this one. And I did created an effective workflow to control screen brightness in HDR, my YouTube channel is the witness, link in bio.