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.
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.