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10" f5.5 Homebuilt Dobsonian

My 10" homebuilt Dobsonian

This scope was constructed during the fall and winter of 1991, while waiting on the arrival of the optics. It has a 10 inch f5.51 Coulter Optics primary, with a 1.83" Telescopics secondary mirror. After receiving an f4.5 mirror that was mistakenly thought to be f5.6 (with a correspondlingly extreme comparator index), I got this mirror. It seems to be good, although I've never had it tested. After using the scope for almost 11 years and comparing what I've seen in it with what I seen in others, I can fairly say that the images are in the upper 50 percentile, maybe even better. There may be a slight turned edge, but nothing extreme. However, the proof is in the pudding, and I've seen one of my best two views of Jupiter through this scope. Certainly worth the $150 I paid for the primary!

Other hardware includes Novak heavy-duty mounts and trunnion rings, an excellent JMI NGF-3 focuser (which replaced the helical Telescopics focuser I originally had on the scope), Telrad, Parks 8x50 finder and some rings I got from Rex's Astro Stuff. I was very pleased to have achieved smooth motions in both axes, due no doubt to chance more than any skill on my part.

Although not exactly "hardware" ("software", maybe?), I also made a black Lycra/Spandex light skirt (shroud). The first one I made was just about right, only a little too small... So, I made another one and it fits great. It has that nice "drum tight" appearance when it's in place. The best part was the look I got from the lady at the fabric store: When I asked for some black Spandex, she asked what I was making. I replied, "A skirt". She kinda backed up and just pointed across the store, saying, "It's over there..."!

This photo doesn't show the Lumicon NGC Sky Vector I installed, since I kept it when I sold the scope. Although the scope won "Best Telescope and Mount" at the 1992 Deep South Regional Stargaze, I suspect this was strongly due to a lack of competition from more skilled builders...