I've done 2d and 3d copy work and installation shots for artists as well as high volume jewelry product work. For both scenarios I charge a base fee, a per view fee and a delivery charge. Depending on the size of the job and the intended usage/output there may also be a digital processing/file prep fee, too. The base fee is critical because it encourages clients to bundle up a number of works to be done at once and assures that I'm not losing money on a small shoot. I'm happy to do a small shoot, but I'm not willing to lose money doing so. The base fee prevents this. I am clear to price "per view" rather than "per item." If someone wants six views of an earring, I need to charge them for all six views. Light, Science Magic
is a good technical resource.