Serious reflection issues

[sk8king989]

Hi, i'm rendering this model i have, and i'm having a big issue with the reflection of a wood surface. It comes out ridiculously grainy with weird speckles. I rendered a scene about 2 days ago that i really like, and for some reason i can't recreate it, if anyone could help me on how to get rid of the grain and some tips on recreating the lighting in one of my scenes, that would be fantastic.

Here are the images.

Wood settings
- http://img296.imageshack.us/img296/4627/44419352rs5.png

Sun settings
- http://img113.imageshack.us/img113/4299/suneh5.jpg

3 crappy renders
- http://img366.imageshack.us/img366/4826/fukrpx1.png
- http://img212.imageshack.us/img212/236/inter6fw9.png
- http://img360.imageshack.us/img360/2149/inter12sb2.png

GOOD render i tried to recreate in previous attempts
- http://img122.imageshack.us/img122/3...dfasdfseb3.png

So whats wrong?

[dalomar_cg]

Re: Serious reflection issues

Are you using regular lights or emissive materials. Emissive materials aren't sampled the same way as lights, so they can cause some of the artifacts that your seeing. In general though, if you enable Clamp Output and SubPixel Mapping in the Color Mapping rollout, then that will do a lot to help those artifacts. Beyond that you can set one of the color mapping modes to one of the 3 exponential modes and that will help as well.

[savphili]

Re: Serious reflection issues

I believe I'm having similar problems, I can't see your images (as we have some websites blocked here at work) but it sounds to be the same issue.

Here is a picture of my example:


I'm using actual VRay lighting and not emissive materials. How do we get around this problem?

Thank you

[jason.dong]

Re: Serious reflection issues

dont know if you use any bump map. if yes, sugest remove them

[savphili]

Re: Serious reflection issues

no bump map on the wood cabinet texture, just have reflection

[fpedrogo]

Re: Serious reflection issues

Go to the Indirect illumination rollout and disable the reflection and refraction caustics option.

[savphili]

Re: Serious reflection issues

Go to the Indirect illumination rollout and disable the reflection and refraction caustics option.

I'll have to try that, thank you. The refraction caustics option was the only one checked.

[fpedrogo]

Re: Serious reflection issues

I'll have to try that, thank you. The refraction caustics option was the only one checked.

Then, I guess those spot are bad sampling produced by the emissive spotlight in the ceiling. Reduce the intensity of the emissive material and use a omni light in front of the emissive spot. You should not use emissive on small object to illuminate the scene. Emmisive material is very good to give the illusion of an light, but not to illuminate the scene. Emissive is just a material with a very high intensity and the sampling is not as the other regular lights.

I hope this work.