Hi, I need help to get rid of noise on a render I’m trying to do on Cycles in Blender 2.75a. Yes, I know this might probably have been posted like hundred times, yet somehow I’m too dull to figure it out even with old posts and I don’t have a lot of time to try and fail.
I tried increasing the samples, 100, 1000, 2000, 6000, doesn’t really change a lot after 2000 samples. I changed clamp direct and clamp indirect, 0, 2, 4, 10, got worse. Played around with light paths too, I tested with the three presets (Limited Global Illumination, Full global Illumination, Direct Light), also all to 128 and 256 too, really changes illumination but doesn’t seem to be helping to reduce noise.
Some renders I did while playing with the options:
A large room with small window, entirely lit by bounce light and light passing through coloured glass(?) into the room. That’s totally not what Cycles is competent with… Please post the scene file.
I have a few tips just by looking at the settings:
You want your bounces to be at the absolute minimum that you can set them to, not min 8/max 256. I would start by setting the max to 8, min to 9 and the Diffuse/Glossy/Transmission/Volume to 0, and increase them each by 1 until the image has an acceptable amount of GI.
As said, this lighting situation is pretty sub-optimal for Cycles, so in this case I would recommend adding a large, dim area lamp inside your scene, to simulate the bounced lighting.
Hi, main problem of the scene is the curtain material.
For a quick workaround I have mixed it with a translucent shader.
An IOR of 0.55 makes no sense for me, by the way.
It is a difference if you set world background to black or strength to 0, 0 switch background off.
I change some other settings but they are not influence render time.
There is for sure a better material solution for the curtain, may an other user can help here.
The curtain is the problem as mib2berlin says. You try mixing different Shaders. I get good results by mixing Velvet and Transparent. You also increase the size of the lamp to “1” to avoid hard edges in the shadows (may need to increase the strength of the lamp too).
You do not packed textures in the file, so they do not appear here.
I forgot to include the window frame and the rod of the curtain in the second render layer, but you have an idea.
I tried what you said, but I’m not achieving the effect I’m looking for. Thank you anyway.
Thank you all very much for your help. I found out that the thing I’m trying to achieve is not possible to do with Cycles, and that is the reason of the noise, since I think it cannot render caustics. I investigated about this and I found out that luxrender can do what I’m looking for.
I tried what you said, but I’m not achieving the effect I’m looking for. Thank you anyway.
Thank you all very much for your help. I found out that the thing I’m trying to achieve is not possible to do with Cycles, and that is the reason of the noise, since I think it cannot render caustics. I investigated about this and I found out that luxrender can do what I’m looking for.
