Issue: Opacity suddenly changing with viewing angle

[Warner V]

Hi,

I'm trying to make translucent curtain material, but I keep on having an issue: If I view the material "head-on", it's very translucent (say, 30%), but if I change the viewing angle, at about 50 degrees, the opacity suddenly changes to about 90%. So when you walk around in the level the appearance of the material changes very drasticly depending on what angle you have towards it:


low viewing angle


slightly higher viewing angle


material

I've stripped down the complexity of the material to just the minimum, but the issue remains. Now I don't know what more I can try..

Any help would be greatly appreciated!

Warner

[Kalle-H]

I guess that the opacity isn't changing but fresnel is boosting specular intensity at grazing angle. You can test that by plugging 0 to specular slot.

[Warner V]

Specular = 0 does not change the behaviour.

I figure there is some connection with the `Basic Lighting Questions` in my other post: Switching off the Mobile Directional Light makes the issue go away. However, I'm unsure how sunlight could affect this surface: there are many other surfaces in between that should be blocking the sun.

[Kalle-H]

Transparent objects use less precise shadowing. Maybe this is related to this. You can set size of transluency volume via command line.