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cameramanben / LUTCalc

Web App for generating 1D and 3D Lookup Tables (LUTs) for video cameras that shoot log gammas.
http://www.lutcalc.net
GNU General Public License v2.0
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Bug: Display Colourspace Conversion doesn't happen after stop correction #25

Closed neaumusic closed 1 year ago

neaumusic commented 1 year ago

I could be wrong about this, but I believe the Display Space Conversion should not be shifting the entire output line left/right but merely 'tuning' it or 'tilting' it up or down, where 0 always maps to 0, and 100 always maps to 100

My repro: Rec Gamma: Linear sRGB Rec Gamut: Rec709 Out Gamma: Rec2100 HLG Out Gamut: Rec2020

Display Space Conversion: Output Base Colorspace: Rec2100 HLG Convert To: Rec2020 12-bit

In correcting a stop with DCC off, the line shifts left and right, which makes sense, but with DCC on, 0 should map to 0, and 100 should map to 100 no matter what exposure shift happens within those bounds -- I would expect the line to 'tilt' upwards, not move left to right

neaumusic commented 1 year ago

I'm going to close this, I think it does make sense actually, if 100 IRE clips at +2.3ev, and you shift the stops +1ev to +3.3ev, all of those values should be lost with a sharp vertical line, not graduated as I thought they might