View Full Version : please help indirect lighting


lipuster
11 November 2009, 05:47 PM
hi everyone,
I am working on my student film and am at the rendering stage now. I have rendered images using fg and gi in mental ray for maya before. but i've been told it'd take too much time if i use that for my entire animation ( I guess so :( )

looking around threads, I have got the idea that one can fake fg with ambient occlusion. but all i manage to do with ao is enhance details and add smooth shadows.I dont think it can create indirect fill lighting (Correct me if i am wrong here).

so my question is what is the best workflow for creating indirect lighting? should i use fg? should i fake it with a plugin like gijoe? or should i somehow fake it with ao?? which would be most efficient approach??

thanks a lot for going thru this.

- regards


Also, is it better to use mr's inbuilt ao mia ao shader or something like dirtmap?

InfernalDarkness
11 November 2009, 06:41 PM
It really depends on what kinds of imagery you intend to make, but FG is a great tool for indirect lighting. You can animate with it just fine. GI is a bit more render-intensive in mental ray, but FG works for 90% of the time you need indirect lighting.

I always use the mia_material_x's AO, which you can apply texture maps to just fine if you need to.

lipuster
11 November 2009, 06:11 AM
Thanks sho pi,

I am using fg with a dome textured with surface shader as the light source. wrks great. And im using mr's mia texture plugged into a surface shader for ao. strangely, maya's render layers' preset for occlusion does the same thing but ends up taking 4 times the render time....wnder y!!!

one more question though, is it a better solution to use something like gijoe if all i want is fg and no gi in my scene??

thanks :)

InfernalDarkness
11 November 2009, 06:36 AM
GI Joe is a Global Illumination replica, using multiple lights as your sky. It's not necessary if you have mental ray. Used to be that using a few lights was faster than true GI or FG, but with modern computers just using MR indirect illumination is fast enough and looks much, much better.

lipuster
11 November 2009, 08:11 AM
great to know that....:)

thanks a lot man.uve been a great help.

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11 November 2009, 08:11 AM
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