Just can't shift this noise

[stayinwonderland]

I have this night scene. All the buildings are just instances for now. The buildings have a box around them (a box primitive > edit poly > delete the top and bottom so it's like a sleeve) with a glass material applied.

 

Here's what it looks like without the glass (note no noise in the selected building - bottom right):

 

 

And here it is with the glass over it:

 

 

There's a significant difference and it's noticeable on all buildings. But the settings are ridiculous and nothing makes a difference. Noise 0.001, various shadow subdivs as high as 32, IRR at high, LC at 2000, reflection subdivs/refraction subdivs set fairly high. But nothing puts a dent in it.

 

Any ideas?

[braddewald]

What do your render elements look like? Taking a look at the VrayReflection Element and the VrayLighting Element etc. separately should make it clear where the noise is coming from.

[stayinwonderland]

Hmm, here's the VrayReflection...

 

 

What do you think?

[braddewald]

It's really hard to tell at this resolution. What are the glass material's subdivions? Are you sure the glass object isn't intersecting the interior object? I'm assuming you're using a VrayDomeLight -- what are it's subdivions?

[stayinwonderland]

Bingo! Intersecting...

 

 

Only issue is that as the glass moves away from the surface of the vraylight material, the light material gets really dim. Previous to this render the light was set to color:75, this one is 120 and still looks diminished. Any ideas on that?

[braddewald]

That's something I, personally, would take care of in postproduction, as you'll have way more control and realtime feedback. Setting your glass object to 100% refractive will obviously let all the light through, so you can start there and then scale it back until it looks right.

[stayinwonderland]

Oh right. I'm curious how you'd handle self illumination in post from a particular material?

[braddewald]

Haha, that's a good question. I guess that I'd do it the non-physically-correct way and just boost the highlights using a levels adjustment on the refraction pass, then stack the reflection pass on top of it with whatever blending mode looked best (soft light?) That being said it might be easier to try just by boosting the vraylightmaterial multiplier like you are doing. If you keep bumping it up it should eventually get to the right level. Start with a crazy high value like 600 and then take it down as you see fit.

[Ismael]

Make the refraction close to 1?

[stayinwonderland]

Thanks chaps, here's the latest. (I played around with IOR refraction if that's what you mean? Setting it to 1 makes it darker).

 

 

Just need to add more contrast to those reflections by maybe lightening the sky and increasing objects that are able to be seen in the reflections.

[Nic H]

i reckon thats a pretty solid base render!

 

you should get some good results by overlaying / fiddling with the refraction, self illumination, reflection and z-depth elements plus some contrast and colour balance.