The top image on the
right is rendered with an
omni light as the only light
source, and the affect shad-
ows option is turned off.
Notice the black shadows,
no light passes through the
material.
The bottom image has affect shadows turned on. There is a fake caustic ef-
fect but it’s nowhere near physically correct.
Note that the V-Ray light is a special light. Although it casts direct light just
like max lights do, they do
produce GI caustics (max
lights don’t!). Normally
only first bounce GI light
(like the light coming from
skylight and object lights
like our light box) produces GI caustics.
If you want real caustics
when using max lights, you
need to enable caustics in
the caustics rollout (photon
mapped caustics). Don’t do
this right now, these caus-
tics controls need a tutorial
of their own... Just remem-
ber that you can get nice
caustics effects by using GI
and V-Ray lights much easier.
That is why I prefer using
the light box or V-Ray light
over the max lights. You
simply check the GI caustics
option and you don’t have
to care about other caustic