short question about lightsetup for caustics

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

the way vray produces caustics is a little bit confusing for me!

just tested a scene with a directional light - beautiful caustics, and
a spot light with the same settings - no caustics at all? :?

is there probably a difference how vray emits the photons for
directional and spotlights?

2

spot lights’ light is spread out…direct lights r not..when u do photons…its best to use directl lights…at least that’s what i always do…