To connect two cameras you need to open the camera and solder some small wires to all relevant pins. Then we apply a pinhead to the wires, fix it on the outside and connect the pinheads of both cameras via a cable so they act as one camera.
What you need is:
two identical cameras (may be old and cheap, I used two Concord5040, for 10€ each)
The simpler the better. Stereophotography works best if everything is the same except for the viewing angle.
thin copper wire (0.15mm diameter)
a solder iron with tin
two pinheads, number of pins depending on how much functions you want to synchronize
two jacks for the pinheads with cables
Mounting for two cameras
Step 1: Open Camera and Identify Pins
All cameras I know have the case screwed on.
As the screws are very tiny and small, I advise you to work in some kind of box with a small rim. The top of a shoe box is ideal. If anything falls down accidentally it won't roll away and nothing is lost.
If the casing has different screws it is good to glue them successively to some clear tape in the sequence as you unscrew them. This way you can easily keep the track which screw belongs to which hole. I also used small dots beside the holes to identify the used holes.
You could also take some pictures during disassembling, to remember the steps.
Step 2: Open Casing
Then you should check for hidden screws behind lids and flaps.
Then the last step is to release the latches that still keep the casing in place.
To do this you could use your finger nails, or what I would prefer a plectrum. This small plastic thing that is used for playing the guitar. They are cheap, rigid and small enough to go between the casings.
Step 3: Looking for Suitable Pins
From the position of the buttons on the case you already know where these buttons are, but not which pins are really used for a specific action.
In the third picture you see the release-button of my camera, and five pins which are connected to the PCB.
I used a digital multimeter to find out which two pins are connected when the button is pressed. When pressed the resistance between these two pins changes dramatically from >100kOhm to a value near zero.
If pin one and three are connected the camera focuses and if pin two is additionally connected to them the shutter is released. So we need three small copper wires to get this functionality to the outside.
I also figured out which pins of the on/off switch are necessary and tied them also on the pinhead.
It is good to make a small note on this because after a few days you won't remember which one on the pinhead is which...
Step 4: Solder on the Wires on the PCB
Coated Copper wire is isolated to the outside with isolating varnish, so if the wire itself touches anything inside the camera it won't cause a short. To remove it just heat up the end with the soldering iron and apply some tin. If the tinned end gets to big shorten it with a pliers.
To solder the wires to the pins you need a soldering iron with a very small tip. If your soldering iron is to big, wound some rigid copper wire (diameter > 1mm) up the tip of the soldering iron. This way you get a very small tip to solder even smallest points.
Normally you don't need any additional tin, as the pins are already tinned, so just place the trimmed and tinned copper wire on top of the pin and quickly heat it up. That normally only need seconds. Try not to de-solder the pins from the PCB!
Step 5: Solder Wires to Pinhead
I used some breadboard to solder the pinheads to and screwed this small breadboard piece to the housing of the camera. This is important because when you unplug the cables it is quite a big force.
You could also think about directly connecting the two cameras, but I wanted to make them separable again. It might be quite annoying if the cameras were connected all the time.
Use hot glue if you are sure that the wires are working and you don't need to disassemble them again. But you could fix it even on a smooth surface like the back or front of the camera without the need to drill additional holes.
Step 6: Change Second Camera
Step 7: Connect the Cameras
All you then have to do is, mount them on a rail together and take pictures.
Try different distances between the two lenses. Ideal is just about 7.5cm, what closely fits the human eye distance. If you make it bigger, everything looks like in Lilliput, when you make it smaller, everything seem to be bigger than it really is. The small shift from the first to the second camera normally doesn't disturb the view. To handle this you could also mount the second camera head over beside the first. But that is quite an effort.
Step 8: Making Stereo Images
You can get a whole bunch of cyan-red-glasses of cardboard and colored film for a few bucks.
In contrast to the earlier used red-green glasses, this allows you to even use colored pictures. All other methods need much more equipment like polarizing glasses and much more. But feel free to try them too.
You have two single pictures or movies and you could do whatever you want with them.
This link provides you some software to do the conversion. I use the "Stereo Photo Maker" which is pretty easy to use. Just load left image, right image, align the two manually or automatically and convert them into cyan-red colored images which can be saved as jpgs again.
The "Stereo Movie Maker" only accepts MPEGS, but hey that is not a problem, as there are a lot of good conversion tools from all kinds of format to everything else.
So go out and take your pictures in 3D and if you like even make your own 3d-movie!
When will you be on Youtube?