Unlikely.
P-TTL is handled by the body
(It's just that the communication between body and flash is a digital system, but the controlling, measurement, and overall performance of P-TTL is all down to the camera body - hence the massive difference between pre-K20D and post-K7)

Matt

Great results Bob!

Here's my little circuit (for those that are interested!):

Usual disclaimers apply




Possibly need a 1k, rather than 10k. (And excuse the rough diagram and poor numbering!)

Have fun!
Matt

Yes it is, and the Apple microphone is very sensitive too!

(It all depends where you put the iPhone in relation to the camera )

Had another tweak of the circuit this morning - all seems good now!
Now I could build it on a small bit of stripboard, but I might just have a go at cramming in surface mount components into the connector itself (just for the sheer challenge )

Components required for each side of the trigger (one set for shutter, one set for focus): BC547 (or equiv), 1k, 100nF x 2, BAT85 (schottky diode). Circuit diagram to follow...

Matt

Had a little tinker with the scope and breadboard...

...pretty close to a working circuit with minimal components
Couple of caps, a diode, a transistor, and a resistor. It's just on the edge with the iPod Touch 4G at full headphone volume (one step down and it doesn't work). Once I get some through-leaded schottky diodes that should improve it a tad


Interesting feedback loops can be created with the *ist-Ds - the noise of the shutter was enough to trigger the app, to trigger the shutter, to trigger the app...

Just need to refine the components (as I was a little short of spare bits'n'bobs!)

Matt

That'll be because the electromagnets still have to be engaged to keep the sensor still. It's just that the sensor plate won't move when vibration is detected

Once the electromagnets are disengaged the sensor plate drops and moves around on its own

Matt

It's the SR mechanism - the sensor is floating on a magnetic 'bed' that is controlled by the camera. It does make a light whirring sound.

When off, and you move the camera around the sensor plate can also move - making you think there's something loose inside!

Matt

Ok...

It's outputting a 19kHz sine wave on trigger. On my iPod Touch 4G this is about 1V peak-to-peak (it may well be larger on other devices since mine's a European-let's-not-damage-your-ears version ).

Since it's only peaking at around 0.5V from ground, likely it'll need a voltage tripler (with schottky diodes) into the base of a FET or NPN transistor to trigger the output.

Even with SMD it'll be tight to get into just a connector
But I'll bread-board something up and see what happens

Matt

...I've just had a quick check and it may not be as simple as that circuit shows. Will need to hook up the storage scope

Some additional info...

The circuit within the dongle is probably quite simple

See: http://dynamicperception.com/forums/help-and-support/mx2/bulb-ramping-triggertra...

Shows a couple of NPN transistors and resistors. Reckon I can put all this into a 3.5mm plug (using surface mount components) and make a lead to do the job. Think I'll have a go sometime soon

Thanks for the info and a great sample photo!
Matt