Continuing working on the scene and added some objects. Passed a morning mapping some books (almost everyone from my real library).
Trying to solve the high noise level in the center of the image. I remodeled the hanged lights reducing the number of polygons (it was a rendered spline with 8 sides, now 4 and with less subdivisions) and removed some lights on the ceiling making them smaller, 3 meters long. After 2 hours and 12 minutes (rendered with max buffer, it didn't print the stamp) I reached 67 passes.
There are still some noise on the metal blades of the ceiling, I'm trying to discover what cause it; with a render region I reached something like 300 passes and the noise is stille there...
Bye!