here is what i wrote down at the siggraph render university, on tuning renderings.......
its in note form so it may be vague or even wrong in places (feel free to correct my misinterpretations and spelling mistakes)
xsi_render
AA -3,2 lower threshold value until obviously need to increase min /max levels, at the same time return the threshold to its original position and gradually reduce its value whilst visually assessing the results.
remember to eliptical filter detailed textures that span both foreground and backgound.
also try 4 *4 mitchell filtering.
use shadow maps as often as possible. render options>optimisation shadowmap> enable.
avoid area lights where possible.
AA happens after motion blurr, so be sure to sample motion blurr high and AA low. low motion blurr sampling will cause alot of noise thus AA will be running at its max level in areas that should be soft and blurry.
deformation MB uses a reasonable amount of memory. leave estimate off motion blurr, it doesnt improve speed/ memory use significantly and can give stilted results.
always have scanline on for accelerating prmary rays. unless a lense shader distorts rays.
BSP TUNING> the key to optimisation.
1: set AA -5,-5 it is irelevant to bsp side of tuning.
2: small viewport and R_region
3: logmessages >progress reports
4: open script editor
5: render options>optimisation bsp max depth (24 - 36) number of times space is divided. (binary space partition) tune this first as it has the biggest effect.
bsp max size (10 - 20) max number of triangles in final leaves of divided space.
6: leaf nodes (20 - 40) number of bsp samples
7: view script editor and try to get average leaf size to equil the average leaf size, assuming bsp depth was accurately tuned your bsp tuning is complete.
FINAL GATHERING.
accuracy = number of rays available in the scene.
max radius = max in which final gather ray can be reused.
min radius = inside this area rays present will be used to interpolate the resulting value.
final gather passes work better with blurred textures, this results in less flickering and oversampling. perhaps an automated fx tree process.
FG diagnostics= green is precalculated fg info, red is fg calculated at render time if to few samples fall inside the max radius value. red is only an issue if it is too dense and no green is around to interpolate between.
for net renders final gather maps need to be defined per machine
c:temp$computername
this avoids flickering.
hope that helps your cause.
_sam