32-bit head-scratcher

[YoyoBoy]

I'm playing around in AE in 32-bit mode using 32-bit EXRs. I have a layer that is set to Multiply and I have found that it is possible, by adding a color curve to it, to make it lighten the image underneath it.

How is this possible?

I'm pretty sure I also got a layer that was set to Screen to darken things as well, but I can't seem to duplicate that right now.

[crazy homeless guy]

Are you sure you don't have those flipped? Screen lightens, Multiply darkens.

[YoyoBoy]

Nope. It works properly initially, but then, if I want to radically clamp the channel with a curve by sliding the highs way over to the left, it brightens the layers beneath. Darken works as it should, though.