Lighting issue

[confusedjman]

I am currently using a nikon coolpix p7100 in addition a filming tent and 3 fluorescent lights (all 35W daylight bulbs) to photograph my product for sale online, it is setup as follows: in a white photograph tent with a small white "table" that i place the items on to be photographed
3 "desk lamps" one on the left side of the tent, one on the right side and one in front above where the camera is. (see below)




Please see the attached videos notice that when the diamond is facing forward the heart of the diamond looks black… any tips on how to fix that?
1) DSCN1557.mp4 Video by caratsdirect2u | Photobucket
2) DSCN1558.mp4 Video by caratsdirect2u | Photobucket
I have tried to put the clip light pointed straight down from the top of the cube as well as directly in front of the diamond (as you can see in the end of the second (link number 2) and that did not really help.

 

[minicoop1985]

This is a bit of a guess, but would a reflector help? Maybe make one out of cardboard with dull (emphasis on dull) side out aluminum foil?

 

[Designer]

Opening myself up for being flamed here, but I think you should use more point lighting rather than diffuse. Instead of those CF bulbs and a light tent, why not use bright halogens placed farther back? You could even make some masks using cardboard to just let a small hole of light illuminate the gems. Then as the turntable turns, you would see the gems sparkle.

Also, watch your white balance. It seems off color in the emerald video.

BTW: check out other threads on here for the same topic.

 

[The_Traveler]

My guess is that the black is due to the diamond reflecting the unlit space around camera.
Shoot through a hole in a reflecting sheet.