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Boris9

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    Michigan, USA
  1. Yes, I had a hint that this may be the case when I looked up the eyeglasses prescription notation - turns out, one of the three parameters is the angle: http://www.allaboutvision.com/eyeglasses/eyeglass-prescription.htm So I tried turning my eyeglasses in front of my eye, and sure enough, the sharpness disappears almost immediately. This should not be a huge problem though. My latest plan is to buy a 25mm diameter polarizer filter (they have a part that can rotate), break out the filter, and glue in the prescription lens in its place - this way, I'll be able to rotate it independently of the focusing. However, I want to finish my digiscoping set up first.
  2. Thank you John! That little scope has surprisingly decent image quality - I guess those sharpshooters are particular about distinguishing individual bullet holes from 100 yards The prisms are Bak-4 porro-type, the same type they use in astronomy binoculars. The viewfinder is non-zooming, so the field of view is wide (60 degrees) and quite bright. I haven't noticed distortions when panning, and there are hardly any chromatic aberrations (to my eye, at least). It's basically a half of a decent binocular - so I don't get to view with both eyes, but also don't have to deal with all the alignment issues between the two tubes. I have an idea what a view through a nice telescope is supposed to look like - I live within a short drive from an observatory that has public viewing, and they have a very nice guide scope (a 6" Takashi APO refractor that costs like a brand-new car. The main instrument is a research-grade Planewave CDK 20", which costs like a brand-new house, but it's camera-only). I'm not ready for a full-blown telescope yet, just don't spend enough time observing to justify the expense. Also, I want something that I can take on a backpacking/mountaineering trip.
  3. Thank you all for the information! Yes, currently I view without glasses. It's just that little extra bit of sharpness should make a noticeable difference when looking at the planets at small magnification. I had thought about ordering eyeglasses just for viewing, but my experience with eyeglasses so far has been discouraging. I always end up just taking them off. Thank you so much for the info about Dioptrx, Richard! That sounds like just what I was thinking of rigging myself, but of better build quality. (Except It won't work with this particular spotting scope because of its short eye relief - I just looked it up, it's just 10.6 mm. Sigh). At any rate, now I know what to get when I'm ready to buy a true telescope Still, it answers my question: If Dioptrx can work, and the eyeglasses can work (except for the convenience factor), that means a normal prescription lens will work, as long as I can find a way to squeeze it into the eyepiece. It looks like Dioptrx requires long eye relief simply to make room for the frame. So if I figure out how to get a lens that fits into the scope's eyepiece and come up with a way to attach it there, it should work. Actually, attachment should be no problem - the rubber will hold the lens in place. All I need is the lens of the right size, which shouldn't be too difficult. I can just order a normal eyeglass lens, then grind it down to size. I've worked with polycarbonate before, it's a remarkably forgiving material. Excellent! Thank you so much! Boris
  4. Hello! I'm very much a beginner in astronomy, and doing a very gentle introduction. Don't have my own instrument, but I'm fortunate to live near an observatory that has public viewing. Recently, I bought a small spotting scope to take on trips. I primarily want to look at the Moon, the larger planets, and whatever is visible. Maybe take a few pictures through the eyepiece. It's a 20x50mm scope that costs very little and is light enough to be mounted on a camera tripod. But now I ran into a problem. My eyeglasses correct my astigmatism fairly well (to 20-20), but they are a fancy "three-zone" type, and it's very difficult to position the "zone" focused to infinity into the right place in front of the eyepiece. It's the very tip of the glass. So I'm thinking to ask my optometrist to order a corrective lens that would be round and small enough to fit into the eyepiece, and I'll somehow fix it in there. What do you think - will this work? Are there better solutions? Thank you so much for any suggestions! As a way of introduction, here's a story about beginners luck: The very day it came in the mail (two days ago), the skies were partly clear, so I set up the little spotting scope on a camera tripod right next to our house. I had hoped to see Saturn, but it was obscured by trees. So I just started looking around. Vega was near zenith and amazingly bright, and I could see a lot more stars through the scope than I could with my naked eye. So I called my wife to check it out. She comes out the door, looks though the scope, and within a couple of seconds, gets to see a satellite sailing through the field of view!
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