I've got a camera that doesn't allow any kind of remote shutter release, mechanical or electronic, and I'd like to rig one up for it. My idea is to use some kind of linear actuator Mythbusters style. I've seen them use these things to push all kinds of buttons and triggers.
I've been trying to research it but not finding much useful information, and I'm getting the feeling that if you can't already understand the complicated electronic diagrams and formulae, then you just shouldn't be trying to do this. I did manage to learn that apparently what I need is (I think anyway) called a solenoid actuator, which run on DC current. I've perhaps foolishly ordered a small one from eBay, that takes 12v DC, and thought it would be a simple matter to find a tutorial on attaching an old camera battery charger or something with a switch to use as a power supply, but not having any luck yet.
Then it hit me - I should ask here on good old SMA - there are guys in here hooking up all kinds of stepper motors and Arduino cards - I hope at least somebody can direct me to some kind of resource for learning about how to do this stuff. Or maybe somebody knows of a better way to remotely activate a shutter mechanically? I mean I plan to literally build a camera holder with an arm above it where I'll attach some device to push down on the shutter button when I want it to.
And before anybody mentions it - I have looked into using one of the old fashioned mechanical cable-style shutter releases. I used to have one of them for an old camera - not sure what happened to it but it seems like it stopped working, which according to Amazon comments they all do at some point - most pretty quickly.
Ok, so any advice or links would be most appreciated!
Edit- here's a picture and the info from the eBay page:
"10mm 10N Spring Load Push Pull Actuator Electromagnet Solenoid DC 12V"
Doh! (mixed meme, I know.. )
Somehow I completely missed your second post!! The one where you answered all my questions, even the ones I hadn't thought to ask yet. Excellent idea - ordering from a reputable seller rather than buying shady Asian imports on Amazon with bad/no info listed! Can't believe I sat here sizzling my brain all day trying to figure out all the stuff you had already explained. Though I think I might try the DC jack adapter I found since it has wire leads on it already. Ok, going back in to give your post the attention it deserves now.
I see the power supply you linked only has the 2 blades, no ground. I was wondering if three blade plugs were necessary or not, apparently not. Cool, I ran across foot switches without the ground plug as well.
Yeah, that DC jack does look easier to use! It doesn't fit the power supply I linked from Jameco, but Amazon is recommending a 12V power supply that should fit it. Note that it's a 1A supply, so if you end up using a 3A actuator, you'll need a different supply -- but that sounds really high to me. I'd guess you'll be looking at something more in the 100mA range, which it'd work great for.
Ground pins are another safety thing, but yeah, not super necessary for this application.
It looks like the foot switches you're looking at would make the circuit even simpler -- rather than needing to wire the switch in series with the actuator, you're just using it to turn the power supply on and off. Nice!
Ok, I was wondering how much power it needs - I just want it to push the button, not punch a hole in the camera! I'm also thinking of dipping the end of the push rod in liquid latex several times to give it some padding and soften the contact point a bit.
In the spirit of followthrough I want to update this thread, not just leave it hanging forever unfinished as so many do after a few rounds of Q&A.
I ordered the stuff (though I forgot to get some wire to connect it all together derp!) but before it even arrived on my doorstep I had decided to forget about the plan and just get a camera that has a shutter release socket. I was essentially trying to turn a sow's ear into a silk purse (or however that goes). A word of advice - check to see what kid of functionality a camera has before buying - that GF3 had basically none at all, In fact I've learned it was designed to appeal to users of camera phones and point & shoots who want to step up to micro four thirds with interchangeable lenses, so they made it all tiny and smooth with almost no buttons or controls on it, like an iPhone or something. Everything (what few things it can actually do) is controlled mostly via touchscreen on the back - a touchscreen that stubbornly refuses to fold out in any way, so you need to be standing behind the camera to operate it or see anything. Heh - not even good for selfies!!
Instead I got myself a GH2- known as an excellent HD video camera and with all the functionality I need and then some. Right now it's out on the deck shooting its first experimental time lapse (well, since I bought it anyway). And if you know about the GH2, it can be hacked to upgrade its performance significantly. I was planning to do that, did the research and downloaded all the files I need to do it, but as I was getting acquainted with the camera I suddenly realized it's already been hacked - the ISO goes all the way up to 12,800!! I contacted the seller to ask which hack it has, and he didn't even know it was hacked - was only using it for stills photography apparently.
Anyway, getting carried away here. I still want to try wiring up the actuator and find something to use it for - I have a crazy plan to use it to trigger the remote for the GH2 using the foot switch I bought, so I can have both hands free. But we'll see..
Awesome! I haven't used the GH2, but I used a friend's GH4 for its slow-mo capabilities... I would imagine they have similarly great image quality. Anyway, looking forward to seeing this project whenever it's done!
More followup -
Today the power supply finally arrived and I decided to just do a quick test fit and see if it will make the actuator do anything. Since the project is essentially dead now I wasn't too concerned about possibly destroying stuff - it was all pretty cheap anyway, so I just twisted the wires from the power supply (actually from the power supply adapter) to the wires from the solenoid and tried it. No diode - hey, ya gotta live dangerously sometimes, right? Plus 12 volts can't be much worse than a 9 volt battery on the tongue. It didn't shock me, it worked, and it was just barely strong enough to push the camera button. And I think I actually was pushing the actuator down against the camera to assist it a little bit - not sure it'll have the power when it's all attached to a rig.
Then I realized I had the wrong actuator - or rather the wrong power supply. I was using the big actuator - the one I had originally ordered on eBay - 3 amps. But the power supply must be less - only an amp or so. So I just now ordered the 3 amp power supply I had listed earlier in this thread - that one should definitely do the trick.
The smaller actuator is so tiny I think it would struggle to bend a human hair :
This is them beside the camera I was planning to use, just for a size reference. It's a really small camera (with a big and rather bizarre lens on it just now) - about the size of a point and shoot. Actually it can push the video button pretty well, but it struggles with the big button, which is the one it would need to push.
And when the new supply comes in I plan to do it up right this time - I'll put a diode in there and solder the connections (and make sure everything is hooked up right - this time I just slapped it all together without checking polarity)
Thomas - thanks again for all the help! I seriously could not have done any of this without you. As for the GH2 - it actually wasn't hacked - apparently they come from the factory with 12,800 ISO!! Wow, who knew??!! I've hacked it twice now - currently using Sedna which I'm liking. Now I'm thinking I'll use it for the stopmotion - 16MP is better then the G1's mere 12, and will show less noise in the dark areas. So I might use the G1 now to shoot any BTS stuff. No live video, but it can do timelapse, or I could rig up the actuator to push the remote for it if I do decide to do that Animator Animating thing I talked about earlier. That would be really tricky though - I realized I'd need to have a bash light that I turn on in between frames and switch back off each time I shoot a new frame - this basement is freakin' DARK when I'm animating man!! I honestly think it's getting to be too complicated - I'd rather just concentrate on the animation itself. I don't need to do Laika style behind-the-scenes stuff. (But I'll probably mess around with it anyway just to see if it's do-able).
Here's the progress so far on this project:
More to follow soon.
The 3 amp power supply came in and it works, but there's a delay of a second or two each time. Any idea why? Or - I guess the relevant thing is just - is it normal and is it going to cause any damage? I suppose a brief delay on a 3 second exposure won't do any harm as long as it's not destroying the actuator or anything.
When I get the bracket built (should be today) I'll try it with the weaker power supply, and if that's strong enough to fire it every time then Ill just use it.
Inductors take a little time to charge, so with a higher powered actuator it makes sense that there's a more perceptible delay. I probably wouldn't worry about that.
The way I was taught is that inductors are like electric flywheels, they take a little energy to get started but once they get up to speed there is very little resistance (if your talking DC current that is). I know I have nothing compered to Thomas's knowledge on the subject matter but I just thought I'd throw in my two cents worth.