Samples for Area Light Diffuse... When to increase?

[DriesV]

The Area Light Diffuse material has a samples parameter.
Tonight I rendered a scene with an area light (sphere) as the primary light source.

I rendered it for 10 minutes (realtime) with different sampling levels for the area light:
*16 samples
*64 samples

Both renders look very much alike. The quality of the 64 samples render doesn't seem to be much better. I can't find any trace of this in the KS manual.

When and/or why should I increase the samples on area lights?

Dries

[PhilippeV8]

No reply here ?