Forum Groups
  All forums
    Help & Feedback
      Work in progress
      Finished Art
      Non-Max related

Featured Threads
  inspiration alert!!!
(36 replies)
  Indespensible MaxScripts, Plugins and 3rd Party Tools
(37 replies)
  The allmighty FREE Resources Thread !
(17 replies)
  spam alert!!!
(4886 replies)
  Maxforums member photo gallery index
(114 replies)
  Maxforums Member Tutorials
(89 replies)
  three cheers to maxforums...
(240 replies)
  101 Things you didnt know in Max...
(198 replies)
  A Face tutorial from MDB101 :D
(95 replies) Members Gallery
(516 replies)
(637 replies)
  Dub's Maxscript Tutorial Index
(119 replies)

Maxunderground news unavailable

Matte-shadow object refractions? How in god's name do I do that?!
show user profile  daniel frisbee
In these images, there is a 3d composited wire structure set into a filmed set, with a big diamond. The wire character travels behind the diamond... but the alpha channel doesn't carry the refractions of the diamond...
I've tried as many variables as I can think of but had no luck...
If anyone knows you would be seriously saving my bacon!

This first image is inside max
This one is a render from within max with the video reference background
This is after effects trying to use the alpha channel
This one is with a refracting material rather than a matte-shadow
(I tried many times setting refraction to the matteshadow material but alas no joy...
This is the alpha channel clearly not carrying any refractions...

see what I mean? I clearly don't know what I'm doing, but if there is a setting to include reflections and refractions in an alpha channel that is what I think I need...

read 339 times
6/20/2010 3:41:10 PM (last edit: 6/20/2010 3:48:08 PM)
show user profile  graphix72
Well, I'm no expert, but think about it: An alpha channel will not carry reflections/refractions because an alpha channel is transparency information. So if the surface is 100% reflective, the alpha channel for that surface will be white. If it's 50% reflective, but otherwise transparent, the alpha channel will be medium gray. But the reflections/refractions will not be a part of the alpha channel.
I think you're trying to capture reflections/refractions in alpha, but I don't think that's possible. You will have to do it a different way, I hope some of the experts here will give you a solution. But as far as I'm concerned, alpha will not do what you want.

read 317 times
6/20/2010 4:15:31 PM (last edit: 6/20/2010 4:15:31 PM)
show user profile  daniel frisbee
you're right...
Someone got back to me, it needs to be a separate render pass for refractions... trying it now... very confusing... It's in the render elements bit..
read 309 times
6/20/2010 5:08:04 PM (last edit: 6/20/2010 5:08:04 PM)
#Maxforums IRC
Open chat window