vray glass against alpha background?


#1

hey, I wanted to do something like a glass sphere with a transparent background, that would look alright with whatever background I put on photoshop, but when I select “affect color+alpha” on my glass material (refraction slot), the reflections become really dim.

how do I get it to work as intended?

this is what I get when I render the sphere with refraction affecting the alpha channel, and then adding a gray background on photoshop

this is what I get when saving the file without the alpha channel

this is the result I wanted

any Ideas?


#2

I’m sure there’s a better solution, but I usually get around this issue by saving out separate render passes so that I’ve got a reflection pass that I can use for either a luminosity, overlay, or multiply layer to increase the effect of the reflection’s spectacular highlights. Sometimes I also use a falloff map for the refraction as well (or VRayDirt map), so that I get more definition/opacity to the edges of the object, in which case the reflections there are more pronounced.


#3

Hey Jeremy,

yep, I tried separate passes but the result wasn’t as realistic as the original render. with some manual tweaking on photoshop maybe I’d be able to replicate it, but I was kinda expecting a better solution from the box

but I don’t do much compositing, so maybe using different passes and different blending methods could work?