Please excuse the incredibly simple question - I was learning vRay fine until I hit this problem and I cannot work out what is going on here.
I last used max v4, been out of visualization a long time and just purchased and am using Max Design 2009, I’m on XP 64bit, vRay and I also have RT (all running on an i7 940 with 12gb ram).
Anyway, all those years ago, I used to do interior scenes, and so to learn vRay, I’ve got an incredibly simple scene of a box as a room, 2 windows punched out of 2 walls and a glass sphere (which is hidden even).
I’m trying to show an environment out of the windows (blue skies / mountains etc), and I’m struggling big time to get this to work.
If I set the Environment up using the 3DS Max Environment dialog box, either the colour swatch or the map will be visible through the windows ONLY when I use a 3DS max camera (it won’t work for a vRay camera) ??
If I stick with the 3ds camera and use the vRay Environment roll-out swatch / map, I get nothing (see attached).
And if I use a vRay camera, again, nothing is visible through the windows (they remain black what ever swatch / map I put into either the max or vray environment dialog box).
Can someone please throw some light on this problem (pun intended) as it’s driving me nuts .
it all depends how your background map is “mapped”
In the bitmap options there is a drop box where you can specify “screen” or “environment” try screen and see what that does.
You might be better just mapping your background on to geometry like a plane or a sphere.
the vray environment it’s not supposed to work like that, it will produce gi from a bitmap but it won’t show it. on the other hand max’s background does, as you found out.
if you have exposure turned on in the vray cam, it may be that the bitmap you’re using as background it’s not bright enough and ends up underexposed. it may not be the case, but it happens.
anyway, you usually have much more control comping the backplate in post instead of rendering it. if nothing works, you may consider trying this way
I got there in the end, I tried it on an even simpler image ( a curved plane and one single light) and it does work.
It seems that I need to play more with exposure controls and resolutions/scales, but as you say, I’m not sure I’d do it this way anyway - more likely do something in Photoshop and alpha channels (that how I used to do things years ago - not sure if techniques have changed much since).
on this problem (pun intended) as it’s driving me nuts 
.
