Like many inveterate users of Photoshop, I’ve never really known what the blend modes (found on the Layers palette) do. That is, I know the effects they produce, mostly through repeated usage, but I’ve never really understood the operations they perform to achieve those effects. (It doesn’t help that their names, e.g., Color Burn, Linear Dodge, Pin Light, Hard Mix, etc., are not exactly self-evident.) This blog post lists all of the blend modes and offers simplified technical explanations of each. For instance, here’s Pin Light in plain English:

“Pin Light replaces the colors [in the underlying image], depending on the blend color. If the blend color (light source) is lighter than 50% gray, pixels darker than the blend color are replaced, and pixels lighter than the blend color do not change. If the blend color is darker than 50% gray, pixels lighter than the blend color are replaced, and pixels darker than the blend color do not change.”

That’s pretty enlightening and actually very useful. Read the whole post here.

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