Frozen Time
High speed flash photography is easier to realize than what you may think, and you can achieve it using your speedlite.
[EOS 10D + EF100 f2.8 USM + 550EX wired with OSCS2 and pointing towards the white board that served as background]
Using high speed flash allows you to see things that happen faster than what the eye can record. Although it could seem quite technical and daunting to try, it’s actually quite easy to realize with an speedlite, once you understand the basic principles.
The light in the flash is produced by an electrical discharge on a tube filled with Xenon gas. Hotshoe flashes, being smaller than their studio counterparts, have relatively small flash tubes, which produce big amounts of light in a very brief time. Also, the less light needed, the less electricity used and the shorter the duration of the flash up to 1/60000 of a second for the lowest power setting. In contrast, normal studio flashes have bigger tubes and put out much more light, therefore they have quite long durations. It varies a lot from brand to brand, but light discharge times of 1/250 are not uncommon.
All this jargon is just to say that the small speedlite you already own is the perfect source for high speed photography.
[Do you recognize your daily shower like that? EOS 5D + 580EX on masked softbox]
To achieve the previous image, two speedlites were used in wireless mode, firing in the same A-group and therefore reducing the power needed by each flash to achieve the freezing effect on the drops
Using the flash as backlight we optimize the power needed to light the droplets and therefore we are able to perfectly freeze the scene. A snapshot of a brief period of time.
[todo: explain use of power and how to reduce it]
[todo: shoot comparison image of different power settings]
[todo: triggering methods: the technique of syncing by hand (for everybody) and a sound trigger (for enthusiast) ]
[todo: show how high-speed sync is not high speed flash - clarification of this common misunderstanding]
[todo: shoot some dust flying or other non-water effect... e.g. fairy dust]