Objects with alpha textures makes what's behind invisible

[hansolocambo]

I have an issue and can't find a way to fix it. I'll explain here and hopefully some of you will have the brilliant idea I can't come up with

- As an Opacity texture for beard, hair, eyelashes, I have the usual image with black background, and white/grey areas for what's supposed to be visible.
- To make the eyes look a bit more "alive" I have a layer on top of the eye globe with a Material "Glass Basic White".

In both cases I render in PNG and alpha (transparency).
- If I render with Lighting in Product Mode, I end up with a see-through beard and hair.
- If I render with Lighting in Interior Mode, I end up with see through eyes.
In one case the alphas don't compute properly, in the other case, the Glass Material doesn't...



If I render the image without transparency all is fine (here in Product Mode, but Interior also works). But I often need a transparent background. I just don't get why those materials make the rest see through.



Thanks in advance for a solution, if any exists