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I have an image with two layers.
The bottom layer is full red i.e. rgb = (255, 0, 0) and 100% opaque
The top layer is black (0, 0, 0) with opacity 50% and blend mode normal.
I expect and need the result to be exactly half way between black and red, i.e. rgb = (128, 0, 0) or maybe rgb = (127, 0, 0), depending on rounding.
Instead I get (187, 0, 0).
Now I have two questions:
1. What is the rationale for this surprising behaviour? Other graphics software I have checked give me the result I expect, Photoshop does not.
2. The import one: Can I configure Photoshop to handle transparency the way I expect it to? So that the resulting color is determined by the "obvious" formula
result = ((255 - alpha) * base + alpha * top) / 255 ?
Just looked at colour settings. You haven't got "Blend RGB Colours using Gamma 1.00" checked have you?
If so uncheck it.
Dave
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What color mode and color space are you using?
I get 127,0,0 here:
Dave
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Just looked at colour settings. You haven't got "Blend RGB Colours using Gamma 1.00" checked have you?
If so uncheck it.
Dave
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@davescm: Thanks for your reply! Are these the settings you asked for?
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@davescm: Thank you, that was it!
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You're welcome - glad it is sorted now
Dave