The idea here is for the bikinis to be seen in 3d..that would mean that they would appear to be worn by an invisible person. Meaning, you could see the front, crotch section, and would be looking past that to the interior of the butt section..Am i thinking correctly here? the bikini would be shot as a complete object.?
With a blue screen or a simple outline job in PS, whatever, you would still only read the crotch part with the strings, or hip straps, receding into the turn of the waist and sort of terminating clumsily. IMO, that is really 2d.
I would think that you might need some very high quality, transparent mannequins. Shoot the things on a light table with a harder key light in the front...put the results in photoshop and get rid of any highlights on the clear form and go to work on matching any loss of saturation, sharpness, detail etc..on the part of the bikini that is on the backside of the clear mannequin??? Or, as stated below in DL 's post, wire the crap out of the thing and sculpt it.
Or figure out some way to style these things on a mannequin form and them apply some sort of clear, hardening resin in order to "freeze" that form. Then (somehow) break away the mannequin form and be left with a frozen bikini...yes, a frozen bikini. you could use wax paper, or, a release compound so nothing would stick to the mannequin. Then you would have actual object to shoot and you would be free to do something really cool.
All of this, of course, depends on whether or not my assumption about the definition of 3d is correct.
Seems like just showing the front of the bikini with straps going back into space would not be to exciting, visually. The hip straps would just stop in space. If that's what they want then it's basically a simple outline deal. Could just be shot against white on a body (white body suit) and dealt with in PS.
Sorry, I like to tinker and would probably end up doing something that would let me make a chemistry experiment and perhaps, a large fire...