Help! Huge Noise Problem All Over!!

[Toh]

Hi, all.

This is the image I rendered.

 

[ATTACH=CONFIG]38313[/ATTACH]

 

The problem is obvious. Huge noise problem all over the place.

 

Hardware:

Intel Quad @ 2.40Ghz, 3.25GB Ram

Geforce 8800 GT (graphic card w/ 512 Mb ram)

 

Sofeware:

XP system, 3DSMax 9 + VRay 1.5 RC3

 

Settings for Vray:

Primary Engine: Irradiance map - preset to High / HSph. Subdiv.=50 / Interp.Samples.=20

Secondary Engine: QMC - 32/4

Antialiasing Sampler: Adaptive QMC w/ filter VrayLanczosFilter (size 2.0)

Min Subd=1, Max subd=32, Clr threshold=0.001

Adaptive Amount=1.0, Globe Subdivs Multiplier=5.0,

Clr Mapping: Reinard

 

[ATTACH=CONFIG]38314[/ATTACH]

 

The Scene:

No Vray sun.

I am only using the environment light (7.0 in the VRay renderer setting) + one Vray light placed just outside of one of the windows.

 

Most of the materials are set to high subdivs over 16, the white wall is set to 50.

 

Render Time: close to 13 Hours

 

Resolusion: only 1200 X 900

 

 

It is not a very big img as I was hoping for. But even with a relatively small res setting, and relatively high render setting, I am still getting all these noise. Light cache may speed things up a bit but it is not as accurate as QMC, in fact, I tried with my test rendering and with Light cache it looked gray.

 

Please Help, everyone!!

Thank you all in advance a million times!!

[azeta3d]

i think i ve never seen before such a noisy render!! your settings shouldnt be an issue, what is more, they are too high, for example the max value of the image sampler, over 6 or 8 you dont get any difference. I dont work with quasi on seconday bounces, so i cant tell you if it is wrong, for me light cache is much batter. viewing the image i remembered a project long ago whic was a headache, it was a house modeled in sketch up, exported as 3ds and imported into max, a poligon nightmare!! did you brought that model from sketch up???

Other thing is to check that the geometry is not reeeeally far away from the scene 0,0,0 coordinates, check that, 3d max gets a bit confused when manages really big number coordinates.

And for last check that you dont have any standard/architectural/global material, they often cause some trouble, to check if it is a material problem just put a vray white or gray material in the override slot in Global switches.

Hope it helps you, cheers!

[Toh]

Many thx to you, azeta3d!

 

Firstly, I built the model in Max from scratch, not importing 3ds.

and I always starting building my model from the 0,0,0 point so that it can be easier down the road and more accurate in the end.

But it is good to know that the coordinates can mess it up.

 

Secondly, you are right, I did just brute forced my scene by pumping up all the settings.

So, I changed to Light Cache for my 2ndary engine and rendered it again.

It was much improved in terms of noise, in fact, the dots are all gone now.

as you can see below:

[ATTACH=CONFIG]38318[/ATTACH]

But, now the shadows on the white wall are too brownish, this is exactly why i didn't use Light Cache in the first place.

How can I solve this problem?

(I have reduced the "generate GI" value to 0.5 or 0.6 on the vray property menu for all the brown objects in my scene)

 

Besides, I still wonder why would I end up with lots of dirt in the first one with QMC as a secondary?

When should we use QMC, and when should we use Light Cache?

 

Thank you again, azeta3

[Toh]

oh, just so you know, the rendering time was reduced to a bit less than 4 hrs, by changing to Light Cache.

 

same settings and same scene.

one third of the time with Light Cache.

[stormchaser]

id suggest that you reduce all the settings to do the test renders, and only crank them up high when you get rid of those glitches, you can not afford to wait 4 hours for each render to finish when the rendering is in the test phase.

btw how many subd does vray light have?

Edited July 29, 2010 by stormchaser

[Toh]

btw how many subd does vray light have?

 

Oh, I just noticed that. I didn't change it, so it has been 8, the default value.

 

um, I did use much lower settings for my test renderings w/ a 500 X 300+ res., which took me roughly 2 or 3 mins each time.

 

Thank you for the tip, Stormchaser. I am gonna adjust the vray light and do it again with QMC, I am eager to find out.

Will let you know the result.