Focusing has always frustrated me, especially now that I’m taking a lot of pictures. Humans are not well designed to focus small telescopes with their fingers. Turn the focus knob, and the image bounces around. Wait for it to settle down, and turn it again…
So I built a motorized focuser, based largely on Brian Sumpter’s design. It works great. I bought the servo, switch, and rheostat, but scrounged around for the rest of the parts (iPod case, erector set pulleys, etc.). The breakthrough for me was using a grommet (I had a box of assorted grommets from Harbor Freight) to fit in the drilled out pulley center-hole and over the .5″ focus spindle. I was also happy to figure out a way to attach the servo mounting rail to the scope without tapping any new holes.
I purchased some light-absorbing flocking board to line the tube with (dark tubes=better contrast). That gave me an excuse to break the scope down, clean the optics, and do some maintenance. I took a picture before putting it back together.
…when the moon is out and I do equipment modifications rather than pictures. But here’s a picture of my latest mod, a custom cross hair reticle eyepiece. I drilled a couple of holes in a 10mm plossl eyepiece, ran some audio optical cable on the inside, and stuck an LED on the outside. For the reticle, I used a spider web and a drawn out filament of plastic cement. I hung dimes from the ends of the web to keep it taut while I glued it. Impressive stuff, spider web, but I think I like the look of the cement strand better when illuminated and magnified.
This contraption should help me drift align the scope for better tracking. I’ll test it out in a few days once the moon starts rising later.
Modification successful; Camera disassembled and IR-Cut filter (LPF2) removed. Here are comparison shots (w/o post processing). Left is the modified Canon 1000D, Right is the stock 1100.
Scott's Sky Shots 