Flash'ard: It's alive!

It's alive, and it's got a name!

Meet Flash'ard :-)

 

There is some logic to the name, I doubt I need to explain the first part, but the "Ard"? Well it's based on Arduino. In this case it's a wonderful little board called a Jeenode(V4), which comes complete with the wireless module I need to make a remote trigger.

 

Anyway, it works, and it's now providing lighting for it's own photographs. Currently max sync speed is 1/160th, but I'm working on getting that up higher.

 

The board has two optoislator triacs (the little white chips with 6 pins each) which keeps the delicate 3.3 volt circuit safe from the 300 volt trigger circuit on the Vivitar 283. It has two isolators because it is connected into two circuits on the flash. One that fires it (which is what a hotshoe trigger fires) and one that stops it (called the quench). Controlling the timing between sending the "Fire" and the "Quench" allows you to regulate the power of the flash. I believe all flashes work like this. When you drop the power you don't turn down the brightness, you're reducing the duration of the flash. (Whether you can get to the quench circuit or not is another issue entirely though!).

A full power 1/1 flash is about 1300us (micro seconds, there's a million of them to a second), a 1/32 is about 30us.

 

Close up of the board: www.flickr.com/photos/steve_snaps/4567175228/

 

Update

Sync speed now up to 1/320th, the limit of my D300. This was achieved by increasing the baudrate of the wireless data communications, so has also reduced the range. I am currently testing to see how this will impact the functionality. If it does impact it then I can slow it down a few steps before it come down to the level it was at when 1/160th was the limit.

Done