Basic Intervalometer

Hi Everybody,

First of all I am a complete beginner in electronics and arduino. so please excuse me if my question is silly.

I want to make a basic intervalometer for my canon dslr. Found out on the net that some components are used to make it (transistor/ relay/ opto-isolator)which is bit overwhelming to me at this point.

googled for the shutter release and its shows that 2.5mm jack has three wires, one for gnd, one for focus and one for shutter, if shutter and gnd wires are connected then shutter happens. So my question is why can't we simply connect 2.5mm jack's gnd and shutter wire to arduino's gnd and a digital pin and set the digital pin mode as OUTPUT. Then like a led blink programme alternate that pin as low or high in interval.

would 5v of arduino damage dslr? what i need to do?

Thanks in advance and again sorry if my question shows lack of sense.

Hi, yes, there is a danger that the 5V could damage the camera. I would not want to risk damaging my camera to find out!

However, perhaps it would be safe if the Arduino never exposed the camera to 5V. This could be achieved by switching the Arduino pin between INPUT and OUTPUT/LOW. The LOW would have to be set first, before changing the pin to OUTPUT.

Alternatively, a diode could be placed on the Arduino pin to block the 5V signal.

I would also experiment with different resistors in series with the Arduino pin to prevent any large current flowing.

Can anyone else with more experience with Canon dslr confirm my theory? I would like to do experiments witb my D650 too, as long as there is no risk of damage.

Paul

If I used an Arduino, I'd put the diode in as 10 cents of protection.
Also pinMode( pin, INPUT ) defaults LOW as does pinMode( pin, OUTPUT ) so no fear there.

The Arduino.... you could use it to program an ATtiny45 for the camera and keep your Dev Board.
The tiny45 costs about $1 and can run at 1 MHz on very little battery. You don't need much.

However there are simpler, cheaper solutions as long as all you want to do is ground the shutter wire.

Like connect those wires to a 50 cent security switch and use a magnet to trigger it.
Or use a photoresistor or similar and cover it with your thumb.
Or get some kind of hardware debounced switch and use that.

You can even throw in a gate and make a safety switch to prevent accidental triggering.

An intervalometer is for taking time-lapse sequences. That is why the OP wants to use an Arduino, to set the number of shots and the time between them, which could be hours, even days.

A tiny85 could be a good idea, depending on what other controls and displays the OP wishes to attach to allow the sequence to be set up and monitored.

I was imagining a pot and pushbutton switch as inputs and a 16x2 lcd display. The display would need to have a serial interface if using a tiny85.

Oh for sure a controller would be best then!

Maybe even pre-set sequence(s) to switch(es) and not need the display depending on how much work he wants to do and stuff he wants to carry.

Maybe even use a whole 328P that can be programmed in an UNO then removed and put in a socket in the project.

Hi diy7,
I have a Canon 40D and if I did it (and I may), what about a couple of opto islators!! you don't need to supply any power, just close a couple of switches in the right order! If both switches need to connect to ground, in oder to work then they must be at a different higher potential.

I think I just might look at this a bit more carefully, and keep an eye on this, a UNO would be ideal for time lapse. Depending on what your photographing you may need to re-focus set/focus for every shot.

Just remembered I have a wired remote cable/switch that would be a good start!

Regards

Mel.

Hi guys! I am working on a similar project for my Canon T3i. I have a mostly working prototype here:
http://forum.arduino.cc/index.php?topic=289285.0

I also am curious about the setup to ground the shutter pin. I have experimented with using just a diode/resistor to a digital output pin, but that didn't work. I had better luck using a transistor and using the digital output to close the transistor to ground.

I have hooked it up to my camera many times and so far nothing bad has happened. :expressionless:

I want to include as much protection as possible. Should I use a diode and transistor? Does it matter what transistor or diode I pick? Zener, rectifier, silicon, I have them all in front of me. How do I choose?

Thanks!
Nate