I have a set of H-550/H-430 Ojecoco triggers and one thing they support is "hypersync" with insane shutter speeds so thought I'd give it a quick go at lunch time seeing as that elusive ball of sky fire was showing itself for the first time in a while.
For those that don't know Hypersync works by firing the flash a minuscule amount of time before the shutter opens so, in theory, as the two parts of the shutter chase over the sensor, the part in the gap between them should be seeing the flash light. It (normally) requires a flash on full power, because it needs the flash duration to be as long as possible - I specifically picked the 565EX for the test because it's apparently got a longer flash duration than the Canons.
All shots taken @f2.8 with a 565EX upper camera right, aiming down at the top of his head/back and shooting through my el-cheapo mini softbox.
First up a shot at 1/250, which would normally be my sync speed:
The ambient is a tad hot to say the least. Switch on hypersync on the trigger, take a test shot to make sure its properly synced (it's adjustable with a wheel if there's any black bars), then take a shot at 1/3200:
At 1/6400:
And finally all the way up to 1/8000:
Certainly not something I'll be using every day, but an interesting tool to have in the box on top of ND filters and high speed sync. It's also nice that it automatically learns the timing from the camera and it's tweakable from the wheel, rather than needing to reprogram the triggers with a PC like a believe you have to with the PocketWizard implementation. It does appear to have some disadvantages though:
- Requires the flash on full power - not good for the flash, the recycle time or the battery life
- Results are "unpredictable" - you need to chimp to see the exposure, which can be tricky because you'll only use this in bright ambient, and the LCDs are a pain to see in those conditions. I guess if you use it a lot then you'll know how much "umph" you're going to get out of your flashes at the various settings though and compensate accordingly.
- Possible gradient in the flash exposure - because each part of the sensor is exposed to a different part of the flash output curve it's possible, depending on the shutter speed and the curve, that you'll get a noticeable gradient in the flash.
