I haven't read any of the articles, but it seems to me that you want to set your camera up so that it will take a long-exposure picture that will turn out almost black, and then set off a strobe while the shutter's open.

Maybe it's so bright down there that the smallest aperture possible will still allow in too much ambient light with a reasonably long exposure. If not, though, assuming it's still possible to get flashbulbs, it seems to me that you could hook something up cheaply with a jury-rigged device involving a relay across the hot shoe, a flash bulb, and a 9-volt battery.

Then again, flashbulbs may well be far too slow for this purpose.