It is better than those slave adapters that "look" for a flash, and then quickly activate the flash, since those adapters can be set off by other cameras. If you're at a party, that can be quite annoying.
Step 1: What You Need:
- a sense of electronics
- an Optocoupler with triac output (i.e. MOC3062)
- 2 capacitors ( 10 ÃÂµF )
- 3 resistors ( 500, 1M, 30...80 ohms)
- a casing (optional, I got mine on ebay)
- a battery
Step 2: The Circuit:
-The Optocoupler in the middle isolates the camera from the flash. If you don't know what an optcoupler is or what it does, check out wikipedia first
-R1 and C1 form a highpass. this is in case the output of the camera is a triac. with out the highpass, the current folwing through the led and the camera could keep the cameras triac open.
- The same goes for R3 and C2
- Now R2 is to limit the current though the LED of the optocoupler. you will have to adjust this depending on you optocoupler and battery you are using. Also keep in mind, that there could be a voltage drop inside of the camera which you have to consider! (it took me like 2 hours till I figured that out!)
Step 3: The Case:
I got in on ebay:
I hoped, there was enough room inside to fit the circuit and the batteries.
Well the circuit barely fit, but the battery had to go outside...
if you squeeze everything into the case, please make sure that none of the highvoltage contacts or cables from the flas get to close to those that go towards the camera.
Also after everything is done, measure the voltage on the contacts that go to the camera before connecting it! Better safe than sorry!
Step 4: The Result:
And that is it. you can now connect pretty much any onld flash to you camera and don't have to worry about triggervoltages or anything!
Step 5: How to Use:
I like the PC cord alot, because it gives you alot of new lighting possibilities!
I hope you enjoy. If you have any questiones, just ask!