Awesome Thread and some Awesome Floral Shots and Abstracts here - I am a Nikon Shooter, hence won't play but I take a lot of interest in Floral Photography but I am going back with a lot of new ideas.
Rob, that's so sharp front to back. Did you use focus stacking to accomplish this, or just stopped down (or any tilt)? I can see the flower is arranged to be in the focal plane as much as possible, and it must be stopped down significantly with the black background (typical of stopped down + flash).