Fresnel on two sided material (billboard)

I’m tying to create a mask for my tree billboard meshes to hide the planes that are not facing the camera (so planes that are most sideways will be hidden).

A simple fresnel node does this perfectly, however does not work when viewing the plane from behind (even when i have two-sided material selected).

Example of the mask: - YouTube

As you see, the mask is only working on one-side.

Does anyone know how to get around this?

Hey, I’ve gotta go, but this is how I do it. I can explain in more detail later. You should be able to modify this to use a fresnel.

OK, I watched the video. Now I can write a little more about what’s going on.

The default lighting models don’t know what to do with a backface normal. Default lighting models’ backface normals just don’t work.

Are you trying to set opacity to 0 if abs(camera vector dot normal) is below a threshold? You should be able to use the output from the “Two sided normal” section of my material to do that.

Thanks @Nathaniel3W. In was able to use your two-sided normal to create the mask i needed.

The idea is to hide planes that are near 90° angle from the camera view. The billboard geometry becomes very obvious otherwise.

This is what I now have for the mask: