letmaik / rawpy

📷 RAW image processing for Python, a wrapper for libraw
https://pypi.python.org/pypi/rawpy
MIT License
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Possible clamping of RGB value? #151

Closed imanolooo closed 2 years ago

imanolooo commented 2 years ago

Hi all,

I don't know it is an issue or a functionality that I dont understand. I would thanks a lot any help.

I'm processing an image with a ColorChecker using rawpy.postprocess() and I'm getting a weird behaviour. Although i set exp_shift to the max value (8), when I measure the white patch of the ColorChecker in gimp I get an rgb color (244,250,254). I have tried different configurations that deals with highlighs as highlight_mode and exp_preserve_highlights, but I got always the same value for all the overexposed regions (including white patch). I have tried to disable auto_scale and autobright also, but same result.

Is there anything that is clipping this value?

Thanks,

Imanol