any way to speed up directional lights?

[bernhard]

Is there any option to speed up the raytracing for directional VrayLights?

thank you

[Svetlozar Draganov]

All optimizations are implemented inside V-Ray so one shouldn't do anything from the UI in order to optimize calculations of lights.
Of course there are some options that are exposed to the UI which may help with this like Adaptive Lights, but all those are also enabled by default, so unless you disabled them on purpose they should be already set up.

Can you provide more information about your inquiry, have you got any unacceptable render times due to directional lights?