I finally managed to track down a used Connectix black and white webcam on E-bay, and after a few weeks I was testing and tweaking to my heart’s content.
I quickly realized I was going to need some sort of case to put this thing in so it would attach to the scope more easily.
After rummaging around some old computer equipment at the office I came across an old broken IBM PS/2 mouse. Hey, the dimensions were right… It is really light, the hole at the bottom seemed the right size… Well why the heck not??
As it turns out the hole on the bottom where the mouse ball goes in is the exact size of a 35mm film canister. I had to break off and sand down the plastic that held the ball cover in place. Not too much, as I was going for a tight fit. If fact the fit turned out to be so good that I didn’t even bother to glue the canister in place.
On the inside of the mouse, the Connectix PCB fits perfectly. The webcam cable is about the same size as the old mouse cable, so I could use the plastic guider and retainer that was already part of the mouse housing.
To hold the webcam board in place, first I made an outline with a permanent marker of where I wanted it to stay. Then I eyeballed more or less the best places for the screws to go and marked them as well. Then I took one of the thicker type paper clips and heated up with a lighter and melted guide holes through the marks I had made.
For the bolts, I ransacked a couple of old serial cables. The type that go from the mother board and end in a 9 or 25 pin D connector where you plug in your mouse or modem. These usually have a hex-nut that is the perfect size for this job.
I removed the hex nut with the screw, and the little bolt on the inner side of the 9 pin connector. I used the hex nut on the inside of the mouse and the bolt on the underside to tighten it in place.
The Connectix board is held in place by a strip of plastic I cut out of an old QIC-80 tape box. It was easy enough to cut with scissors without breaking. I made melted a hole on either end with a paper clip and threaded two more hex nuts. This was then screwed on top of the circuit board into the hex nuts already in the mouse body. Nice tight fit, and all ready to close up and pop it on the scope.
And here’s a bottom view of the finished product. It is very easy to align the CCD to center. The fit is tight enough to hold the board in place from an occasional bump, but not tight enough to keep you from putting it back into place with your fingers if the alignment goes off.
Eventually I’m going to try to set up a computer fan on the other side of the mouse so I can cool my… Mouse Cam!
One great thing I discovered is that the CCD chip is much closer to the eyepiece than in the regular webcam ball housing. This has made the camera is very close to par-focal with my Meade 9mm illuminated reticle eyepiece.
Hey! What’s that on your telescope?!? If nothing else a mouse hanging off the back of your telescope does attract a lot of attention. My father and I had a laugh at how ridiculous the thing looks on the LX50. But, hey… It works!
Check my astro gallery for images taken with modified webcams like this one:
https://astroturtle.com/imaging/