Brute Force <-> IrrMap

V-Ray V-Ray for 3ds Max Issues
1

Hello!

I have set up a scene for animation with Brute force as Primary bounce. It looks good so far though rendertimes are pretty high. When I switch to Irr.Map (in order to test how much render time would decrease) the picture looks different. Especially reflections look different.

Is this normal?
Do I have to change any parameter to get the same results as if rendered with Brute force?

Here you see an example:
BruteForce

IrrMap

This is the Testfile (max2008 ):
http://www.mirko-heimburger.de/misc/vrayreflectionissuea001.zip

2

That’s what happens when you compare exact vs. approximate rendering methods:

3

Yeah, you are right! Thanks for the link.

4

It looks to me as if the cylinder material has glossies set to be calculated within the IRMap, but reflective GI caustics are off.
Is it at all possible?
The difference in the reflected part isn’t, imo, justified by the different GI method, particularly in this simple case.

EDIT: i didn’t realise the file was there. and yeah, as ONLY method, the irmap will not bounce more than once (who’s the rhyming daddy!:lol:), hence lose the reflection of the floor. Add at least 1 secondary bounce (with any method you prefer) and the issue is cured.