Hair and Fur noise

[atagino]

I have to create a room with Fur, on walls and floor. I've notice after adding hair and fur using corona using a material. It created a lot of noise in the scene especially in the ceiling area, where there is no hair at all. Any help would be appreciated.

[romullus]

I think this is expected, GI has to work harder when bouncing from each individual hair, therefore Corona needs much longer time to resolve noise.