Yes, the built-in Tone Curve presets are “partial” (in that some affect only the RGB channels - and others affect only the L channel) … and ONLY the “Linear” preset affects ALL channels.
- It’s in order to (help) make all users aware of the implications of the new separation of the Luma/Luminance channel (from the RGB channels) that I contend that the Linear preset would be much more helpfully labelled; “Linear (RGB + L)”
I’m finding there’s quite a bit of nuance in the result of separation of the Luma/Luminance channel from the RGB channel (for which, previously, it was combined within). I reckon it will take me some more experimentation (and pondering) to understand this properly.