Rendering an animation with moving objects - please advise

V-Ray for 3ds Max V-Ray for 3ds Max :: General
1

We’re rendering some animations now where pretty much everything moves. The camera, the lights, the objects…

Therefore we’re using an irradiance map workflow with use of prepass/rendering method. Pretty much the same thing as described in a tutorial here:
http://www.spot3d.com/vray/help/150SP1/tutorials_anim2.htm

Now my question is: In the final step of the tutorial is written to keep only Irradiance map and turn off light cache. Somewhere I heard or read that if you’re using light cache for glossy rays, you can’t really do that. Is it true?

What we’re doing at the moment is that on the final rendering pass we set the irradiance map according to the tutorial above and we still keep the light cache but change the mode instead of Single Frame to From File and we use the saved light cache file that was made during the 1st rendering pass. Is this a correct workflow? To me it doesn’t sound right because even if we render many images in an animation, the light cache file is only one for a whole animation.

Thanks a lot for any advice and explanation on the matter.
David

2

Keep light cache as single frame for both prepass and rendering if you are using glossy rays. AFAIK this is because the glossy ray information is not stored in the irradiance map when completing the prepass. If you choose not to use glossy rays you would just turn off the secondary GI as all information is stored in the Irradiance map as per the tutorial.

3

Perhaps this will help as it gives more information on using light cache with glossy rays or not. http://www.workshop.mintviz.com/tutorials/flicker-free-animation-using-vray/

4

Thanks guys. We will certainly use light cache with glossy rays. Render times easily tripple without the option while the image doesn’t change much in 95% of scenes.