You may want to try a transparancy map. You can use various shades of gray to get various levels of transpaency. BUT, I've always had trouble getting convincing translucency. Check this out. (I learned VRay entirely through internet tutorials. There is a ton of great stuff on the web).

http://alzhem.brinkster.net/sub1/tutorials/tutorial6_en.htm It usually looks weird.

http://www.aversis.be/extra_tutorials/vray_basic_material_settings_03.htm

sparch,

I don't have a tutorial suggestion, but I have found the quickest and easiest way to render that effect is to use a vray light material. Then right click the object and under object properties adjust the objects visibility anywhere from 50% to 95%. Most of the tutorials suggest materials that are beautiful, but take forever to render, and in an architectural setting this usually does the trick.

so in your case you would want 90-95% visibility, since light going through isn't a problem (the material would produce a glow of light) you just need to see slightly through the material.

hopefully this helps.

purrrrrr............

you need to try sub surface scattering (or SSS). It's how your hand is semi transparent when held over a flash light, or how the edges of a candle 'glow' with the flame behind it.

It's incredibly processor intensive, though, so expect crazy render times (not to mention learning to do it - any top 3D renderer will have the capabilities).

Honestly, I've never had a case where I thought it was worth it. You could probably get a good result playing with the transparency and some subtle blurry reflections.

There are some good sand blasted glass mats out there and they are probably very similar to this (notice how the objects closest to the plastic are visible, but blurry?).


I'd start with a box with a window, put in the plastic, then add a self illuminated object the size of the room (so it evenly lights the plastic panel), add a few objects in between and start practicing.


If you want to cheat, just make them very opaque and add the blurred furniture after you are done (that's the quick and safe way).

try goofing around with the blur parameter in the refraction field.
setting it around 0.7 with 5 sample insteda of the default 8 should be enough to make it grainy. Set the refraction value to something around 121, and the diffuse color to white.
Works most times.

that's me right there, smoking at the entrance...

i would try simply making the object you want to appear transluscent - actually glow by making it a lightsource or just give the material some luminosity. then, if you want to show silouette's of things behind the wall - edit some basic shapes/transparencies in photoshop. sometimes i think it's easier to get a photorealistic solution w/ a more basic rendering option like that. just because the object in real life would allow light to pass through - doesn't mean you have to create it that way in Max or whatever software you're using. sometimes it just takes too long to create materials that actually respond as they would in real life - and the final result often isn't worth it.

thank you all for your help.
this is follow-up update

at first, I used vray light material. and i forgot to make it transparent. it seemed as shadow couldn't appear over the light source.

at last, I just used generic viz/max material, changed diffuse color, transparency, translucency, shiny. I put omni lights, but I didn't have time to put omni lights on a set location. next time, I will model lightbulbs and put vray light material on lightbulbs.

I have few questions to ask.
once putting material on a layer, how can u get rid of it?

once editing material to be little bit transparent and put material on a layer, visibility I set on layer's properties... does it get over ridden, or is it still effective? transparency setting and visibility setting work together?

where can you find blue parameter in a refraction field?
i couldn't find it.