How many lights before Adaptive option appears

Was wondering when the New adaptive option appears under the Raytrace options? I see it only appears after a certain number of lights in a scene. What is that number and does it only work with certain lights?

Hi SHoutzager,

The Adaptive Lights option is always visible in the advanced Raytrace / Optimization options.
It’ll affect the raytracing in the scene even when the number of lights is lower that the Adaptive number specified.
All direct lights are affected by it.

Konstantin