I belive they are big because of the filter. Try turning off filtering

yes I tried very hard to get as much fireflies as possible :D
Tok about 3 hours for 64000sp on gtx 460.

I always believed that the color of the pixel is the sum of all samples divided with the number of samples.
But then the fireflies would lose intensity as there is more and more samples and that ...

tnx for the quick reply

Is there a region render option ?

Can the mesh light be used with direct lighting or must it be path trace.