Sample Quality ?

[XtremeCoryGordo]

hey, in max 9 im using mental ray 3.5 and had some questions... In the sample quality rollout for rendering, can someoen explain to me what the spatial contrast setting is all about, and what is the fast rasterizer option that says if it is enabled it ignores the min/max pixels and spatial contrast....if i select that and ramp up the pixels and the shades will that give me beter results than the other thing... and what isthe difference between the floating point frame buffer and the other one thats 16bit. I tried looking these things up but i couldnt find anything on mental ray 3.5, which seems to have different options and calculations than the other ones.. thanks