Pin Light

Alt/Option+Shift+Z

Contrast, Non-Commutative, 50% Gray

Replaces the colors, 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. This is useful for adding special effects to an image.

Output = max(Base, 2*(Blend-0.5)) // For values of Blend > 50%

Output = min(Base, 2*Blend) // For values of Blend ≤ 50%

Pin Light can result in different, incongruous areas of color. To best understand this, look at the inverted blend triangle. Note that the overall brightness is relatively stable, while there are odd sections of slightly unexpected colors.