Interior lightning setup

[ISurg]

Hello,
we are making an interior animation and I'd like to ask for some tips about lightning.
There is a big shopping center and I'd like to find a good way to light it. I tried playing with standard Max lights, but they are harder to control if you want a good seamless lightning and I ended up with quite high number of lights, which slows rendering a lot. With few VrayLight planes it's easier to get a good lightning, but when placing them just above the ceiling, ceiling gets in the shadow. Also, in some places if I don't want lights to cross geometry, i have to use quite a number of them, which slows down rendertime even more than standard lightning (although the result looks better ) So, maybe someone has a few tricks to share about interior lightning, which is suitabe for animations?

[DanielBrew]

For a large space with lots of direct and indirect lighting like a shopping centre I think VRay plane lights with 'store with irradiance map' checked would work the best. Just remember to up the subdivs to something like 64. When you 'store with irradiace map' you can have several hundred lights rendering almost as quickly as 1 or 2.

Storing with the irradiance map also means that your animation will render much more efficiently as you will be able to use a similar workflow to Vlado's tutorial http://www.spot3d.com/vray/help/150R...ials_imap2.htm

[MoonDoggie]

Based on the Aversis tutorial found here page 2
http://www.aversis.be/tutorials/vray...ighting_02.htm

to quote it:

The consequence of this is, that shadow quality doesn't depend on the Vraylight subdivs anymore, but the it is controlled by the GI settings, namely the irradiance map (and QMC GI for secondary bounces).

So I don't believe the subdivs matter when storing with the imap.

[vlado]

As Daniel pointed out, the VRayLight subdivs do matter, even if using the "Store with irradiance map" option.

Best regards,
Vlado

[MoonDoggie]

I suspected that from my own tests however I read from two different tutorials that they didn't matter. I'll try and find them and update their authors

[RErender]

Not much of a time penalty when they are stored so I crank em up to 75 as a rule.

[ISurg]

Big thanks everyone for the suggestions, I'll stick to the VrayLights.
I also have a few questions about rendering. Is it any difference which frame of animation I use to calculate light cache (first, last, any in between)? And when calculating irradiance, should I use precalculated light cache as secondary engine to speed up calculation of glossy rays (use light cache for glossy rays ticked)? Or maybe this does not have an effect until the final rendering?

[Micha]

My experience at Vray for Rhino is, that many Vraylights in a scene cause a slowdown of the LC pass. Is the same effect seen at Max? For mass light scene I try to use the emitter material instead, because than it dosn't matter, how much are used.