Thanks for your link but no one explains the chrominance scale, most of my well shot clips tend to bottom out at 0.3 which suggests that this is the normal range of values whereas some clips fall below. All the tutorials explain Luminance which I understand (and yes i know they are related as well). I have used the Video limiter and set it to 100% and the control that was set to -30% is set to zero, this seems to clamp the Luminance signal in the 0.3 and 1.00 limits, with what appears to be no visible artifacts or banding. I guess I need to understand saturation a bit more to control some of the peak signals in the highlights and shaddows regions. Loving getting into grading at this level of detail but it is a steep learning curve.
I dont use , trust or like BC Levels filter.
I posted up examples and screen grabs recently in a discussion on same thing.
I start with LEVELS which automatically clips your Luminance. Right on 100. I tend to always drop it to 95% ish
Using Luminance WFM - I will use Use RGB Black INs /Outs to set low blacks .3 (If need be)
Next I switch to the RGB Parades and check Color (Chroma) Luminance. Red is usually the only culprit and I will deal with that in LEVELS using Red (R) Highlight (Input or Output)