AcademySoftwareFoundation / rawtoaces

RAW to ACES Utility
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A couple of questions about white balance #117

Open ilia3101 opened 4 years ago

ilia3101 commented 4 years ago

I am considering adding EXR export support to MLV App. It is a raw converter (lightroom type app) for the magic lantern raw (MLV) format. Recently, EXR export has been suggested and I like the idea.

I want to make it possible to export ACES compliant EXR files, so I have a couple of questions about how rawtoaces does it:

My understanding is that rawtoaces does the following: converts raw images the ACES AP0 colour gamut, using either matrices generated from spectral data or the adobe coefficients, then exports to scene linear EXR - is my understanding correct?

And what is the white balance method used? Is it the bradford transform? And does it adapt the specified white point (from the user-specified grey box for example) to be at the ACES white point (somewhere near D60)?

TLDR: what are the rules about white balance for getting ACES compliant EXR images?