Lighting glass objects can be tricky. It seems like the glass wants to reflect everything around it, in fact, that’s exactly how glass reacts to light. So the trick is not to light the glass itself, but rather you need to light the surfaces that the glass reflects.
In this example of dark field lighting, the wine glass is sitting on a sheet of tinted glass, the background is black foam core board attached to a white wall. In a darkened room, there is very little for the glass to reflect. Two speedlights illuminate the sections of the white wall on either side of the black board, this illumination is what the glass reflects, giving it a clear shape.
Check out the lighting diagram below for basic dark field lighting. (You can click on the image to see a larger version.)
Once I had this lit correctly, I added the Goofy Pez dispenser. I had a friend hold a speedlight with a gridspot a little behind Goofy’s head to give him a rim light, and I held a white card to the right of the camera to reflect some light back into his face.
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