I'm rendering a very simple scene in mental ray. No lights, just an incandescent whiteboard to use with Final Gather to illuminate a cylinder. (see picture)
I wanted to make the shadow on the floor much more visible, but the light falls off too fast before it has chance to illuminate the ground below.
Is there any way to make the light from the whiteboard reach further?
I've tried editing the Final Gather falloff start/stop parameters, and I can only reduce it further, not icrease it.

I've also tried scaling up the amount of light from the whiteboard, but to get it to reach further than the cylinder, the front ends up being completely washed out.