Shutter Mouse

After looking around for a cheap shutter remote to do some nighttime photography, I found that there is no such thing as cheap in digital SLR photography. Canon wanted upwards of $30 for a simple switch on a 2.5mm stereo jack. I checked out ebay for something similar to what I wanted only to find that some company is making cheap knock off’s of Canon’s RS60-E3.

Let the chaos begin!

The first thing I wanted in my remote was a long cord. There’s nothing worse than waiting upwards of 2 minutes to take a photo and then to have your head (or a ghost image of it) in your time-lapse photo. I decided to make it modular. To solve this requirement, I chose to have the remote be detachable from the cord.

The next requirement I wanted was to have the device be handheld. I found the images of Canon’s remote looked like something that was made to be activated by your thumb. This didn’t look very efficient for fast focus and shutter release, so there had to be a design change. This brings up the next requirement: Separate focus and shutter buttons. This device could be used in daytime photography, so I wanted something that I could push one button to have it focus on the subject (or tell me that the objects in the frame are unable to be focused upon) and then another button to take the picture at the moment I wanted it to. I also thought that this should be able to lock the shutter open in Bulb mode. With the flip of a switch, the shutter should stay open and with the press of the auto focus button or the deactivation of the switch, the shutter should close.

After looking for nearly an hour at Wal-mart, K-mart, and Radio Shack for a body for the remote, I came nearly empty handed. There was nothing that fit my requirements. I did however find the answer to one of my problems, the cord. Radio Shack sells a spiral wound, 3/32″ 6′ (2.5mm 2M) headphone extension cable. This fit the camera perfectly and was plenty long to get out of the frame when taking a picture. I also picked up a small switch for the Bulb mode pictures. Back at home, I went to searching the net for something that would fit my hand, have two buttons, and best of all, cheap.

Inspiration happens in odd ways

After surfing the net for a while, it hit me. “Look at your hand dumb ass.” A computer mouse had two buttons, was easily modifiable, and had to be easy to hold in your hand. I found an old ball mouse that had been given to me and proceeded to modify it.

Nothing like the smell of Solder

Here’s what you’ll need for this project

1. Mouse
2. Soldering iron and solder with rosin core
3. Flux
4. Stereo 1/8″ Y-adapter cable -> 2 mono RCA ends
5. X-acto small saw blades and handle
6. 3/32″ - > 1/8″ stereo adapter
7. 3/32″ 6 foot male - female extension cable
8. Carbonic Acrylic(CA) Glue
9. [optional: CA Kicker]
10. 1/2hr time

Here’s what I did to modify the mouse.

1. First, prep the mouse for modification. After thinking about it, there’s not a lot of room inside this little guy. Space can be made by taking out the guts off the circuit board. Capacitors, Oscillators, and even resisters can be taken off of the board. Two things that should stay should be the momentary switches we’re going to use. Don’t take them off, they will come in handy later in the process. Remove the mouse cord too, we won’t be needing that in the future.
2. Now that we have a slate to work on, lets see what we can attach wire to to make our switches work. Flip the PCB over and follow the traces from the switches. Find a decent solder pad that you can use to attach your wires from the stereo cable. Use a multi-meter to find out what contacts you will need to use. I found that once you found your spot your are going to use to connect your wire to the switch, mark that spot with a pencil. I found this is easier than having to run wires under the PCB. Now, cut off the stereo male connector from that Y-adapter you bought. Inside both wires, you should have a ground and a insulated wire. For my camera, I had to figure out what circuits needed to be closed in order for the auto focus and shutter to be closed. I found this page detailing what connector position was what circuit. Strip the wire insulation away only 1/4″ or so, too much will lead to problems. Twist and tin the leads to make it easier to insert them into the holes in the PCB. If the holes you have selected are not clean, the wire will not go in very easily. Take a straight pin and clear out the holes if needed. If they’re really plugged, you will have to drill them out. I tried sucking the solder out of them with braided wire, but it didn’t work as well as I wanted it to. The straight pin worked well for cleaning out the holes. I wired the wires from 1(ground) and 2(auto focus) to the right mouse button and 1(ground) and 3(shutter) to the left mouse button. Solder your switch for bulb mode on the same contacts as your shutter. Double check the solder points to make sure the wires didn’t move before the solder cooled. A cold solder joint leads to intermittent problems and lots of headaches.
3. Testing: Now that you have soldered everything up, it’s time to use the multi-meter to make sure your switches still work. I found that I had a short in the closed shutter circuit no matter what position the switch was in. It turned out that I needed to cut a trace to isolate the circuit. I removed a section of the trace, tested the circuit again and everything worked as planned.
4. Now that you have everything in its place, its time to make sure everything fits. Route your wires so they don’t obstruct your screw holes and mount your connector in the front of the mouse. I found that the grommet on the back of the connector fit almost perfectly in the hole where the mouse cord went. I had to trim the top of the connector to make the buttons work correctly. I found that a small X-acto saw worked perfectly for cutting the hole in the side of the mouse for the switch the switch to the main PCB with a drop or so of Carbonic Acrylic glue. I also used a drop or two of carbonic Acrylic glue on the PCB to secure it in the mouse and to stop it wiggling when the switch was moved.
5. Close everything up, and once again, DOUBLE CHECK that all your connection are working and are activating the correct circuits with a multi-meter. If it’s all working now, you should be able to plug the 3/32″ - > 1/8″ stereo adapter into your 3/32″ extension cable and into your camera. Now enjoy that you’ve saved over 1/2 if not 3/4 of the cost of a canon cable and have a more functional remote shutter switch for a fraction of the price.

Pictures: ( click for full size)