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InfraredAD
07-23-2003, 08:02 PM
So, now that I've got some experience in dealing with reflections I'm still not getting what I wanted, but I figured an actual render just might help in explaining this, so, here goes:

See the sphere on the left and the green reflection it's casting of the green sphere on the right? I want to take the green reflection (on the gray sphere) and make it in grayscale. The trouble is that the sphere on the left is using a gray base color, and using a grayscale color causes the reflecting color to be the color of whatever's being reflected (confused yet?). Things are different if the sphere on the left was red; the reflecting color would be red. If I didn't define the reflecting color and the left sphere was red, then the reflection would be blue. So basically I'm trying to get complete control over the reflecting color using a grayscale object.

http://mypage.iu.edu/~smetzel/diftesting.jpg

Is this a Photoshop trick orrrr...... ?

I'm using Cinema 4D v8.1... And thanks for whatever help anyone can give me.
flingster
07-23-2003, 09:00 PM
dunno...why not composite two images...one gray reflection on sphere and one green...then drop into photoshop?
:shrug:

object buffer maybe?
Per-Anders
07-23-2003, 09:10 PM
use compositing tags, the green sphere needs to have "seen by camera"on, but "seen by rays" off, then dupe the green sphere where it is, change it's material to grey, and give it a compositing tag that has "seen by camera" off and "seen by rays" on :)
flingster
07-23-2003, 09:14 PM
Ooooh you clever geezer....!!
its so simple when you know how...:eek:
InfraredAD
07-23-2003, 10:01 PM
Oh that is a cool trick! Heh, thank you SOOOO much. Too bad I couldn't just strip the color channels out of the object's reflection (or the material's reflection). This flippin' rocks! :buttrock:

Now, on to bigger battles.

He's a tricky one he is folks, but he's good, oh yeah, he's good.:thumbsup:
mrblifil
07-23-2003, 11:11 PM
That is a great solution, but you can also render multipass and alter the color of the reflection pass in PS or AE, grey would be easy, just strip out the saturation.

Kevin
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