Here’s the official description of Pin Light mode:
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.
If you found it hard to wrap your head around that description, you’re not the only one. I tried — for quite a long time — to come up with an example that illustrated the concept, and either I’m getting something wrong, or the description isn’t quite right. I’ll share with you what I tried, and maybe some of you smarter people can tell me where I went wrong!
I started with two identical layers, one flipped 90 degrees. Both layers have black, white, and shades of grey in between. The middle grey is 50% (128-128-128).
With the horizontal layer on top, set to Pin Light, (and both layers cropped a little bit to see the unblended original bits) here’s the result:
Ummm. Let’s look at that again. I’ve marked the two top sections as “blend layer lighter” (than 50%) and the two bottom sections as “blend layer darker.”
Focus on the top sections: “If the blend color (light source) is lighter than 50% gray,” — which is true for the top two sections — “pixels darker than the blend color are replaced, and pixels lighter than the blend color do not change.”
So the pure white stripe across the top makes sense — the darker pixels in the vertical layer are all replaced with white.
But the second, light grey stripe…? The vertical white section doesn’t change, since it’s lighter than the grey. But according to the definition, it seems that the vertical black and darker grey sections ought to have been replaced by the lighter grey blend color. Hmmmm. The same contradiction seems to exist for the darker grey area as well.
Anyone want to shed some light on this? (No pun intended.) Download the sample .psd files if that helps you.
Well, just because I don’t understand Pin Light mode doesn’t mean that you or I can’t use it! Let’s start with a picture of an extremely cute dog:
Put the dog on top of a white background and set the dog layer to Pin Light mode.
Whoa! All of those not-quite-white greys have been knocked out and replaced with white for a very edgy, overexposed, you-see-this-a-lot-in-magazines-and-CD-covers look.
And since Pin Light replaces all of those light greys with the base colors, I could even give Socks (the dog) a weird, retro-esque polka-dot effect. Fun!