One of the main reasons I got my first DSLR (Pentax *ist DS) was cave photography. While I've seen many admirable cave photos they were all carefully set up and posed. Beautiful as they were they lacked something - a captured moment. It's not like cavers didn't capture moments in caves it's just that they did it with point and shoot cameras and on-board flash. I wanted to do better than that.
At first I thought that high ISO will do the trick but it was no where near high enough to freeze a moment with available light. So I started experimenting with flashes and optical triggers. It was a step in the right direction but a cumbersome one. Caves feed on light and bounce very little of it so flashes had to be in visual range of each other. Another trouble was that whenever someone took a snap with their compact camera it would trigger the flashes.
Around that time (6 years ago) first cheap radio triggers were emerging on eBay so I decided to try them out. One thing they lacked was range and reliability but that was fixable with antenna mod - a piece of wire that was soldered to transmitter circuit board.
|Three flashes, three receivers (one glued to the flash in the middle) and trigger with white wire antenna (click image to enlarge)|
|A case with flashes, triggers and space for camera (click image to enlarge)|
What I like most about them is that they don't mind the trigger voltage of flash, they are very small and if fellow caver brings along compact camera he can snap all he wants - my flashes will be ready when I need them.
The triggers have their vices and virtues but once you get to know them capturing moment in cave is actually doable. Why just doable? While triggers do their part most of the time, prior to taking photo one has to pair them with flashes which then have to be put on right spots so they provide good light while not getting in the way or getting damaged.
Some pictures that I couldn't have done without the radio triggers (click an image to enlarge and browse):