How to use iRay in low-end pcs

Padone

hi all

When I first used iRay I was frustrated from the huge resources requirements it apparently had. When using Blender with Cycles I could get excellent results with minimal resources. Then I gave a deeper look at daz scene elements together with monitoring iRay behavior with gpu-z and I understood why.

1) Textures - daz items in general are far away from being optimized as far as textures are concerned. I saw horrible use of texture mapping especially on scenes. While characters in general are just oversized far away. You can get a huge leap forward just by resizing textures to a more optimized size for the scene. I mean, unless you plan to shot an extreme closeup of the character eye it is very unlikely that you need a 2048x2048 pixel texture for it. For the average shot 512x512 is optimized enought. You can use xnView to resize a bunch of textures in a single go.

2) Lighting and convergence - In my tests I found that using a single uber environment with backdrop lighting is by far the fastest way to render with iRay. You can adjust the backdrop map to fix the sun position and change it to get different type of lighting. As far as convergence is concerned, it seems that iRay has a hard time converging dark zones in the image. But, since dark zones are less sensible to human eyes, then I often get believable realistic results with just a 25% convergence ratio or less.

Just by using the above two tricks, that is, texture resizing and uber lighting, I was able to get the barefoot dancer rendering in about ten minutes in a very entry-level pc, intel n2840 4 gb ram + nvidia 820m 1 gb ram. With D|S using about 2 gb ram and 250 mb video ram. (yes, you read it well, 250 mb video ram)

 

Hope this helps. Bye