One of the difficulties with jewelry is perspective and depth of field interactions; on the one hand, you likely want to shoot at an angle (as in the cross example immediately preceding this posting), but Depth of Field limitations throw the foreground and background out of focus too badly for your taste*.
This can be corrected by using a tilt lens or bellows. Such lenses or bellows (for example, Nikon PB-4) are fairly expensive and require experience, but can greatly increase the effective depth of field**.
Here's a 45 degree perspective example showing the dof increase** with an 8 degree tilt lens at about 1:2 mag:
With the right lens tilt, an entire tilted plane can be in focus**.
Dave
* short dof on a perspective shot isn't necessarily bad as people automatically use such clues as an indication of how large the subject is (see the miniaturizing effect of tilt lenses.)
** I should better say something like "tilts the in-focus plane so a tilted flat subject can be in focus" - thanks to Lowell G for pointing this out.
The gear is an inexpensive used bellows ~$40, a MIR Pentacon Six 65mm lens (80mm would be better) ~ $65 ,and a Hartblei tilt adapter ebay ~ $125
Last edited by newarts; 12-11-2010 at 08:05 AM.