Problem with correct colours in python script

[programmer_ceds]

(12-07-2021, 11:40 AM)david Wrote: Many thanks for the replies.

I have carried out more tests this morning. The results are absolutely consistent. I used RGB and Grey images (which are converted to RGB), 8 bit precision, but have tried up to 32 bit floating point with the same results. I measured the result after converting the layer mode from soft-light to normal.

With colour selected as white: FFFFFF     255,255,255
the measured result is:           C5C5C5    197,197,197

With colour selected as red:   FF0000     255,0,0
the measured result is:          C50000    197,0,0

Similarly for green and blue.

With colour selected as grey: 7F7F7F     127,127,127
the measured result is:         616161     97,97,97

The result is consistently 0.77 (decimal) of the correct value.

Any suggestions for tests to resolve this problem are most welcome.

Could you post the image that you are starting with - or if you are creating a new image the exact steps that you are using (including the settings under Advanced Options of the Create a New Image dialog?

Not doubting what you see, we just need to work out the difference between what you are doing and what Ofnuts and I are doing.

What settings do you have in Preferences/Colour Management?