Congratulations! And best wishes for the proposal (and what follows). A hand shot of the happy fiancée wearing the ring would be much appreciated.
Couple of tips for photographing diamonds:
1. Use macro mode and set the focus mode to a relatively narrow zone in the centre of the image. You want the diamond in focus, not the box
2. Don't use flash - try to get as much natural, diffused light as possible (or very very bright artificial lighting)
3. Set the diamond on a neutral grey background. White doesn't give enough contrast, and black messes up the camera into over-exposure.
4. Take a few pictures from the top, as well as the side
Who knows, after taking a few more shots you may even find you enjoy it!
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