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royterr
11-21-2008, 06:10 PM
I have an arealight emiting only specular with quadratic falloff.
the hotspots on my lit geometry look super grainy with 32 samples for my AreaLight.
They get smoother with a sample value of 500 witch is a crazy number.

playing with the reflec samples of my mia_material does nothing.
render globals samples do nothing.

i always had this problem with bright area lights and objects near them.
any ideas on how to solve that problem. Thanks.

http://sor.typepad.com/files/areaartifact.bmp




scene (http://sor.typepad.com/files/miareflectionproblem.mb)

Ash-Man
11-24-2008, 09:21 PM
Sorry, so you looking for smooth (sample) or is it the object is too bright (hot spot)

royterr
11-25-2008, 04:16 PM
smooth sample

eikonoklastes
11-26-2008, 08:01 AM
256 High Samples is about par for smooth close ups. Then what you want to do is either raise the High Sample Limit or bump up the Low Samples to around 64. These determine how good the light looks in reflections/refractions.

Your AA is too low. Set it to 0/2 or higher.

256 High Samples with AA 0/2 and Gauss Filter 3/3 gives me a perfectly smooth image.

visua
11-26-2008, 11:05 AM
Do you have the mia_mat hooked up to the shading-node's shadow slot?
If the answer is yes, break the connection and see if it helps.

royterr
11-26-2008, 03:11 PM
Do you have the mia_mat hooked up to the shading-node's shadow slot?
If the answer is yes, break the connection and see if it helps.

i did, still the same problem


256 High Samples is about par for smooth close ups. Then what you want to do is either raise the High Sample Limit or bump up the Low Samples to around 64. These determine how good the light looks in reflections/refractions.

Your AA is too low. Set it to 0/2 or higher.

256 High Samples with AA 0/2 and Gauss Filter 3/3 gives me a perfectly smooth image.

so 256 is a reasonable number for close objects?

eikonoklastes
11-27-2008, 09:44 AM
so 256 is a reasonable number for close objects?Well, that entirely depends on your available render time. I tend to render with 1/3 AA so I keep the samples lower at around 64 and only bump up further if the grain is very noticeable. Learn about the Low Samples parameter too. It's a good way to tweak the quality/render-time balance.

royterr
11-27-2008, 02:39 PM
but the problem is that even if the object is far away from the area light, still u have graininess it's not a "close up" thing

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