Something weird with Firefly anyway. On some scenes it was definitely rendering faster than the unpatched version, but on others it would render a few buckets quickly then suddenly slow down, even at parts of the scanline is still on the same object, with no other bounding box intersections and no raytracing surfaces (and no strand based hair in the scene). Part of nerd's advice is counter intuitive for a REYES renderer (which Firefly is supposed to use as its main architecture). Increasing the bucket size should speed up, not slow down rendering speed, although it would use more memory. Additionally it seems odd that even with polygon subdivision Firefly still seems to perform smoothing of polygons. If a 'pure' REYES method had been implemented, this should not be necessary. That is a part of the speed benefits of the REYES method. Perhaps most telling is the fact that REYES is intended to be extremely resource friendly (it only needs to load one object and one texture at a time, although some practical considerations impinge on this), whereas Firefly is patently at the opposite extreme. Bill