Rain and EyeAdaptation?

Hey Folks, so I’ve been trying to figure out this Eye Adaptation. I’ve been tasked with reverse-engineering some Rain FX for our project and this one node is throwing me off. We’re trying to increase the rains visibility while retaining the EyeAdaptation.

Some believe it’s set up correctly (Image 1, “Sector 1”), but I don’t understand what’s happening. I tried searching for information on it, but I’ve come up empty.

The goal here is to have the rain brighten in darkness, and darken when its bright. It looks like no-one uses EyeAdaptation within the material, since its globally applied through Auto-exposure.

The documentation here is for PostProcess.

Image 1:

Image 2:’s a video testing out just the EyeAdaptation on a cube. It looks like these values cause the cube to vanish when the scene brightens. No idea what that is.

How can I establish the range for Eye Adaptation if possible?

Exposure changes from some negative to some positive values, so it looks like you need unpack it into some different range with clamp or oneminus, or something…

Anyway I think you should change not opacity, but maybe reflection of particles material.

It sounds like you would get better results if you made the material receive light from the environment, rather than try to control its brightness manually.