Material for skylights industrial/commercial building

[OzBoz]

I'm trying to create a material for skylights you've in mostly industrial buildings. From the outside they appear not really transparent but they do let quite some light through.

I looked at a lot of pages but they were mainly for old versions of V-Ray and for example this image I just edited the refraction glossiness to 0.5 which does give a nice blur but not the white tint needed. I also tried to create a two-sided material with a layer of white on top of glass but don't seem to get it right. Also experimented much with fog but maybe it's the values I use but can't get close to what I want. Also tried just to take a 'plastic' and change the opacity but that doesn't seem the right way either.

Maybe a V-Ray oracle here can give me some advice what the best way is for such material. Basically it's quite opaque (so you won't see all dirt I guess) but does let a lot of light through.

Thanks in advance!

[iva_mancheva]

Hello OzBoz ,

The material used for industrial skylights is usually fiberglass or polycarbonate (they look identical). I suggest you to try with the Polycarbonate library material, it is located in the Glass Category in the Material library. If you find it to be too reflective you can reduce the Reflection glossiness and it will appear more white.
Please let me know if you get the desired result.

Kind regards,
Iva

[OzBoz]

Hi iva_mancheva ,

I already played with the polycarbonate (and now a bit more) and I'm getting there. It's just hard to get it 'white' enough. First I did some test with just different refraction values, than I noticed the kind of studio lighting doesn't really give a good idea so I changed that.

Than I played with the 'thin wall' setting. I think that's not really meant for solid windows like I create but it does give a closer result to what I want, combined with 0.1 refraction glossiness.

Don't think it's really the right approach but since this will be more like an illustration I'm fine with it. I did upload the test file if you like to play a bit and maybe know a more accurate, nicer solution but that's mainly because I like to learn how to do it the right way. File: https://fizion.nl/files/test_polycarbonate.zip

Thanks for the help and enjoy the weekend!

Oscar

[iva_mancheva]

Hello, Oscar,

One trick I can think of is duplicating the back surface of the skylight panel and moving it up a bit to place it into the panel's geometry. Then apply to the surface a Two sided material (with a close to white color Generic material for the Front and Back) and play with its translucency (you can leave the polycarbonate material of the skylight geometry as it is in your scene or maybe make it a bit more reflective if you wish).
This way the material appears even more white:


Kind regards,
Iva

[wzfwzfwzf]

Diffuse color white, reduce refraction.see GIF image

[OzBoz]

Diffuse color white, reduce refraction.see GIF image

Nice! Thanks, looks like a nice solution, gonna try!