I'd like to know the blend formula that Photoshop uses in it's Normal blend mode. Any documentation I find it says it replaces the layer's color by the brush color, which is true but nowhere does it say what happens with the alpha value.
For example, when I paint with magenta (255,0,255) with a 50% opacity and then paint cyan (0,255,255) also at 50% opacity on top of it, I get 85,170,255 with an alpha value of 0.75 as a result color. So obviously opacity of the brush color has a stronger influence than the opacity of the layer.
Just like the other blendmodes the Normal one has to have a formula to calculate the final color, does anyone know it?
Thanks in advance