Very strange colors popped up in render

[kevin miller]

Figures, I need to have this progress render for tomorrow morning and now I am getting these weird blue, white, yellow artifacts. I am using max 2009 and the render settings have not changed for awhile. Things were going fine. The only drastic thing that changed in the scene was I have been messing with the glass material trying to figure out how to get environment reflections and make it somewhat highly reflective since there is no interior. I am using a low setting on FG and mid level AA. No GI and I am using the MR Sunlight and sky with a skymap in the slot. Like I said though, it should not be the render settings as they have not changed for over a week and I have done other renderings. Actually, come to think of it, I am working on another project and have not seen any issues. If someone could get my arse from being cooked that would be great!

[kevin miller]

Solved. It was the glass material. Something to deal with me playing around with environment and reflectivity. I reset the material and it is fine. Now to try and get a good sky reflection on the glass.

[Macer]

I usually use this technique. It takes a bit of fiddling to get it right, but once you've done it the first time it only takes a few seconds:

 

http://mentalraytips.blogspot.com/2007/02/clouds-with-mental-ray-sky.html

 

Very useful for animations too. Just by adding clouds to your sky it should give you more interesting reflections than the plain sky. Of course if you're after specific reflections, just bang an image onto a plane and position it correctly in your scene.