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xvariant
03-19-2010, 08:21 PM
Im reworking an old project with some new lighting and i cant seem to get rid of the grainyness on the back wall and other areas, i turned up the samples but it helps it a little bit but not much but also makes the render 4 times longer. any help would be much welcomed!http://www.khuongtran.net/images/lab_khuongslight007.jpg

high res link http://www.khuongtran.net/images/lab_khuongslight007.jpg

mister3d
03-19-2010, 09:35 PM
Seems like lightsources have low shadow samples. This is the first thing to check. Then you can turn up global samples. And them , is this won't help, make the noise threshold of a global sampler higher, like from 0,05 to 0,001 etc.

kelvincai
03-20-2010, 05:23 AM
for anti aliasing, 0/2 should be enough for interior scene. And, I assumed it is a skyportal light, so shadow samples is the first thing to check, as mister4d suggested. And, if you fg, try using a higher interpol size for a quick check. Large piece of white wall usually need higher fg interpol size.

mishurov
03-20-2010, 08:17 AM
Seems like lightsources have low shadow samples. This is the first thing to check. Then you can turn up global samples. And them , is this won't help, make the noise threshold of a global sampler higher, like from 0,05 to 0,001 etc.
Nope. Shadows in the picture are very smooth, and dispersed points are in regular grids, it seems like reflection samples. The Author needs to look for all materials in the scene with reflections and add them more samples, or to turn on the interpolation.

xvariant
03-21-2010, 07:42 PM
i fixed the wall problems, but when i started to do a render, i noticed i got a lot of artifact under the table and i cranked up the samples, but they dont seem to make a difference
http://www.khuongtran.net/images/shadowhelp.jpg

hi res http://www.khuongtran.net/images/shadowhelp.jpg

mister3d
03-21-2010, 08:25 PM
Isolate the problem. You can render different passes and locate it.

CHRiTTeR
03-22-2010, 11:29 AM
I wouldnt worry too much about rendersettings at this stage, finish the modeling, texturing and lighting first. Its best you start tweaking your samples when everything is ready.

azazel
03-22-2010, 01:24 PM
To me it looks like either skyportal related problem, or not enough samples in ambient occlusion shader, if you use one. Try replacing the skyportals with area spots, and see if the problem persists.

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