Having flashes not pop at at an event while shooting group photos is really aggravating, especially when the Bishop is being kind enough to stand there while this would-be photographer fights with the equipment at hand to at least get some shot worth having…
Not having a budget to acquire real RF wireless remote triggers that support the wireless Nikon CLS protocol has driven the investigation into using alternate means, including the use of wires, to extend the range of wireless CLS (formally AWL per Nikon, a subset of CLS) controlled flashes.
Some perusing of the web turned up this interesting video where an AVR microcontroller was used to trigger an SB-600 flash using a plain old LED, which validated my strong suspicion that an LED could be used to wirelessly trigger a CLS flash.
I only need to locally repeat what the camera sends for each remotely controlled flash; there’s no need to reverse engineer the AWS protocol or even use a microcontroller. A phototransistor, a regular transistor, a red/near IR LED, some resistors and a power source should be sufficient to re-create the CLS master pulses at some remote location. (I’ve not drawn up a schematic yet but eventually I will…)
Here is a photo of the successful first attempt at triggering a remote flash:
The trigger LED, which has a wavelength of something like a 800-900 nm, can be seen just above and to the left of the flash.
Now remote extender and the Picaxe smarty trigger needs to be built into a box/systen that allows the use of ethernet cables to distribute the signals and power to allow multiple CLS and dumb flashes to be used and remotely fired using only the on camera flash as the CLS master.