On one of the pro photo forums some of my correspondents wrote-in asking If I had to shoot on slide film I would use a frosted plexi surface and would have foregone the shadows. How would you have brought the paper backdrop to a clean white 255,255,255 (not just the background "wall" of the sweep, but also the "floor" of the sweep where the products are resting) without blowing out the white and frosted products at the same time. The client wants a clean white with subtle shadows. They are not looking for the frosted plexi look with reflections.
Another of my correspondents wrote-in complaining about my answer to the first guy, saying My client has also specified absolute pure white (in this case for digital applications) like you said below while at the same time keeping the natural shadows immediately around the product to give it weight and depth etc. So please, Joe, how would you light an object in a situation like this? Especially with products that are very close to white themselves and, in addition, may be reflective? He (and myself) was asking for help, advice, information or constructive feedback about this, so please do share.
Okay, now you both owe me a substantial consulting fee.....
You keep the white paper white by not using white paper, you use matte finish white Formica. You don't "sweep" the Formica either, you lay a 48 X 96 inch sheet FLAT on a table made from a 48 X 96 plywood and two sawhorses, light the back with a 4 foot bank and the product/foreground with shoebox banks & reflectors (mirrors). Control your flare with black cards and gobos (shoot with a long lens). Once the surface and the product have been cleaned, handle them only while wearing cotton gloves, every finger print will show.
Proper still-life technique is something most photographers (even my generation) never learned! Best to leave professional photography to professionals, send me checks in the amount of your fee!!