What i am trying to do is make a ir beam remote for my camera. i have figured out the camera part it is 3 wire, 1 is common and 2 and 3 are focus and take picture, so connecting wires 1 and 2 will focus and connecting wires 1 and 3 will take a picture… is there any way to have arduino connect 2 pins together? so when my ir beam is broken it will take a picture. i wrote simple code for the ir beam it seems to work when i break the beam my led comes on i just cant find any info on connecting or shorting 2 pins together to complete a circuit.
Check on what the camera really needs. You may find that it will accept some logic level signals in place of shorting pins 2 or 3 to “ground”. Simply connecting the Arduino ground to pin1 of the camera may allow you to drive pins 2 and 3 directly. A low on the appropriate Arduino pin may cause the desired camera function to work.
Most cameras use pulled high switches. For example, Nikons. I use NPN transistors (one for focus, one for shutter) for this and it works fine. I’d be concerned about exposing the ATMega’s output high voltage to the camera connections, which is why I use the transistors. Cheap insurance. Any small signal NPNs will work: 2N2222, 2N3904, 2N4401 are common. Use what ever you have or is cheap. The NPN’s bases are connected to Arduino pins - output a 1 to both of them to take a picture.
To answer your question, it’s possible to tie them together though you lose the focus only feature. Also, some auto focus cameras will open the shutter before focus has completed, thus getting a blurry photo. Putting a couple hundred mS of delay between focus and shutter helps to prevent that.
By the way, if I was totally concerned about protecting the camera, I’d use opto-isolators. Probably unnecessary, though.
