Author Topic: Results from Color blend mode are not right  (Read 1529 times)

Results from Color blend mode seems to be wrong.

As seen in the image, SP2 doesn't just replace the hue, it also affects the luminance of the bottom layer. Compared to the Photoshop result is at least unexpected. Converting such image to grayscale (via black and white conversion or grayscale conversion) reveals the increase in lightness.

As the point of Color blend mode is to adjust the color, not the luminance or saturation this is pretty problematic.

I think there might be same thing going on with other HSL / LAB blend modes as well: https://en.wikipedia.org/wiki/Blend_modes#Hue.2C_saturation_and_luminosity

I'll just leave it here :) https://forum.allegorithmic.com/index.php?topic=13545

(TL;DR: color burn doesn't work as expected, either)

Have you tried turning your Photoshop document in your example to a Linear profile and activate linear blending? Does it give you a closer result?

Yes, I can't get it to change the luma of the result (CS6).

To my knowledge the definition of Color blending mode is to change the chroma of the underlaying color, not the luminance or saturation.

This behaviour (and others like it) makes it impossible to:
a) adjust chroma locally for color zoning etc
b) fake color correction adjustment layers with solid fill layers
c) match and use cross-application results (like PS <> SP/SD)

To me this behaviour is just wrong no matter if in Linear or sRGB space, please look into it.