Is it possible to use Photo Booth with a USB digital camera?

I'm an illustrator, and I have enough need for photos of myself and various objects that I have a Nikon digital camera permanently mounted on a tripod in my studio. Is it possible to use Photo Booth as a viewfinder, so that I can see the camera's-eye-view of whatever I'm shooting? I know that literally, it can be done, because I currently use Photo Booth to shoot micro photos from a Celestron USB digital microscope. So why not input from a Nikon? Can it be done? If so, how?