color bleeding

[hoegmikkelsen]

Hi,
I hope someone can help really soon, because I need to get this image done.
My problem is, that the floor is reflecting a lot of its color to the walls.
That means that the room is getting very dark, since the floor is made of dark wood.

Is there any way to prevent this, or do I have to make 2 renderings (one with the floor and one without the floor)

Thank you

[dalomar_cg]

Re: color bleeding

At the moment there isn't a direct way to solve this, but the work around is rather simple and won't add any really time to the whole render process. Color bleeding is an issue with Indirect Illumination. So the work around is to render all of the GI solutions (IR and/or LC) with a "neutral" material (ie one that helps with the color bleeding), save those solutions, set V-Ray to use those solution as opposed to calculating new ones (set mode to From File), and render as normal.

In the future there will be something called a V-Ray Override material which will allow for different materials to be used for GI, Reflection, Refraction, and Shadow calculations. All you'll have to do with that is put the "neutral" material in that GI slot.

[hoegmikkelsen]

Re: color bleeding

Hi,
Thank you so much for your answer.
The problem is, that I am not quite sure that I am doing it the right way...
I change the material that is reflecting the color to something neutral and then render the image.
Then I save the map under Light Caching (which is set to be my secondary engine, first is QMC)
Then I turn the reflecting material back on and load the map under Light Caching, and then render it again?
Is this completely wrong or?

[dalomar_cg]

Re: color bleeding

Yep, thats pretty much it. The first time through, you don't need to render the whole image...just the Light Cache part. Under Global Switches there's a little check box labeled Don't Render Final Image. You can use this for exactly this kind of thing so that you don't waste time calculating the image that you don't need. Remember to switch it back once you've render the Light Cache info.

As a note, because you're using DMC for primaries (which won't allow you to precalculate with a different material) you won't see nearly as much of a change compared to using something like IM which can be saved like the LC pass. Something to keep in mind if it still isn't coming out how you'd like.

[hoegmikkelsen]

Re: color bleeding

Hi,
wow thank you so much for the tip.
I changed to IM and now it finally worked.
Thank you so much for this big and quick help.

Line

[brandonlynne]

Re: color bleeding

I've also been annoyed by color bleed, and Micha suggested that I simply change the Saturation setting located here:

VRay Options > Indirect Illumination > Post processing options > Saturation

the default is 1.0, but I find something around 0.6 works well to correct for me. (I know this makes my renderings less realistic, but it often more clearly communicates my material choices in an environment for client review).