Q: What do you call it when there are a dozen Silky Sharks circling the boat at night?
A: Snorkel time!
Seriously, this is a relatively risky way of interacting with the Silkies. They are drawn to light like moths to a flame. Time in the water is limited to a strict 30 minutes. If they start bumping you (and they will), it is time to get out of the water. But the opportunity to see these guys up close and personal is unforgettable. My big failure was to leave the camera in autofocus mode. There wasn't enough light for it to lock and consequently I got very few images, even though there were photo-ops galore. I was screaming through my snorkel at the camera, but the rest of the boat thought I was screaming at the sharks. Silly crew.
I tried an unusual strobe angle. I was again using twin strobes, but since I was looking straight down and I didn't want to get flat images, I put the strobes below the camera by about 1.5ft and pointed them towards the subject. It gives a dramatic highlight to the dorsal fin.