niosy when GI is off

[cdavis]

I have a scene which is a 360 animation of a car with a camera pullback. I had GI on ( BF primary & LC secondary) & its fine looks great, but I dont really need the GI because I have to render it in an external render farm & the GI isnt making much visual difference. But when i turn it off my renders become noisy.

any one have any idea why?

Thanks

Chris

[vlado]

It depends on what kind of light sources you have, but GI can really help to clean up noise from mesh lights.

Best regards,
Vlado

[cdavis]

i have 1 area light & a dome light only with a exr running through the tex node

[vlado]

Yes, textured lights also benefit from GI, especially if they are close to other objects. You can probably just leave the primary bounces on, and turn off the light cache, and maybe use lower settings for the GI.

Best regards,
Vlado

[cdavis]

ok thanks ill try that. If i do need to do a light cache file is that easy enough( to precalculate it to be used on a render farm)? I havnt done it before & am up against it here, so dont want to get into lots of trial & error.

[vlado]

Calculating and saving the light cache file itself is easy enough, but it would be best to ask the support guys at the particular render farm for more information.

Best regards,
Vlado

[cdavis]

whats the standard way of saving alight cache?

[Zdravko]

you can either use Auto Save File option or the Save button (after you calculated the map):
http://www.spot3d.com/vray/help/maya....htm#renderend

[RobPhoboS]

Cheers for the tips and info guys, I'm also rendering some stuff which is just using the dome light+hdr, and some vray rec lights. I turned off indirect illumination and just fiddled with the adaptive DMC settings until things looked ok.
I had to ramp them up quite a bit for things which were highly reflective in the scene but the render times are fine for the animation.

[cdavis]

Cool. thanks for the pointers. Just ended up with no GI & up'd my domelight samples & it looks great.

Thanks

Chris