FS5: understanding HLG vs Slo2/3

[klfi]

FS-5 ... my intention is avoiding noise when recording extern with Shogun Inferno 4KDCI to ProResHQX


Picture Profile 10 enables HLG1, HLG2, HLG3 and colorspace 2020 or 709.
If those are used it allowes to change ISO setting down to 400 and up. (menue camera/paint)

Log 2/3 have ISO 2000. White at 60 IRE .........2 Stops over to avoid noise will mean zebras about 75-80 IRE.

To avoid noise does it make sense to
a.) use HLG PProfile10 (HLG 1,2,3) and Colorspace 709......insted of PProfile 8,9 (=slog2/slog3 ... with overexposing 2stops and correction in Resolve using -2 compensation lut)
b.) reduce ISO lets say to 500
c.) set white to 90/95 IRE (Zerbra)
c.) grade in Resolve as "normal" rec 709 (not as HDR) ... sightly raise contrast and lift/gamma/gain ..... done

Will noise be reduce using this workflow becouse ISO is reduced and iris will be opened up (similar to EI workflow on FS7...EI 2000 down to 800 an open iris +1,3 stop).

What are the mistakes in my thoughts and in this workflow. Do i loose DR ?

thanks for help
Klaus

 

[Cary Knoop]

Noise is a characteristic of the sensor and the AD converter, it has nothing to do with the OETF.


What I would recommend is to expose right, avoid tinkering with all kind of unorthodox settings in camera and use the Resolve colorspace transformations what they were designed for.

With respect to HLG versus log. The only issue is the blacks, the bottom of the curve is Rec.709 and the nature of the Rec.709 curve is that the bottom has very limited code values assigned to it.
This is somewhat mitigated by having 10 bits but for a full HDR spectrum log is still better.