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timwetherell

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Everything posted by timwetherell

  1. If you're going to shorten the tube, might be worth considering fitting a 2" diagonal so you can use 2" EPs and get a huge field of view. My finder is a short focus 66mm and with a 2" 40mm ep has a field of view of almost 8 degrees. The downside is that it may introduce weight issues depending what your mount etc is
  2. That's 3 degrees in Somerset, probably be lucky to have 1.5 up in Harrogate However being discrete stars rather than a fuzzy, I rekon it would be possible. Visually I found M7 reasonably easy to see but the globulars nearby M69 and M70 were a real challenge. Totally impossible under all but the very clearest haze free skies and even then right on the limit of my vision.
  3. Very pleased to have been able to capture M7 last night - only really visible for a couple of weeks in midsummer and even then only about 3° above the horizon. Stellarium suggests it should be possible for anyone south of Newcastle with a really good south horizon.
  4. Very pleased to be able ti image this from the UK, just 3.5° elevation on the meridian!
  5. timwetherell

    M31.jpg

    From the album: Astrophotography

  6. My obsy is quite small so at the extremes there's only about 400mm between the EP and the circular wall. At first I was worried this would make it a bit tight but actually I really like it because I can lean on the wall when observing which really helps with comfort and steadiness at the EP - it also lessens the chance of spilling my brandy
  7. For me it's blow any dust off with a hurricane blower, then gentle wipe with un-perfumed facial tissue moistened with pure ethanol. If there are any water soluble marks remaining I breathe on the lends to fog it and again wipe with tissue. My main rule is one wipe per tissue then get a new one so I can get through half a box cleaning the objective! Only needs doing about once every two years though.
  8. I have a nice WO 1.25" erecting prism - it's outstanding for low magnification terrestrial use but does degrade the image somewhat above about 100x. The biggest problem using it for astronomy is that you get a really big diffraction spike from the cemented joint between the prism components. And of course the extra glass and surfaces drops the contrast a little. Great for looking at ships at sea though
  9. I've been very, very impressed with the Esprit 100! Excellent optics for the money I'm sure you'll enjoy it
  10. I've done this once or twice with my refractor when looking for Sirius B in the UK to get the very least scatter possible. I could convince myself there was a tiny difference but to be honest, the difference between good seeing and bad was a million times greater than anything the diagonal introduced. On a good night the pup is pretty clearly visible and on a bad night, it's just not there It is a literal pain in the neck for higher objects though. And my observatory is quite small so there's only just room for my head between the wall and the eyepiece when focused all the way out like that
  11. I have an owl that likes to hang around when I'm observing. I bet deep sky objects would look pretty spectacular in his f1 eyes!
  12. An atmospheric dispersion corrector will do quite a bit to improve views of low planets. I've had some pretty decent views of Jupiter when only 15° elevation since I bought one a couple of years back. It's tempting to think that the slight yellow and blue fringes above and below jupiter don't make much difference to the middle bit, but of course they do! It's like applying a 20 pixel motion blur in photoshop across the whole planet. With the ADC, you can definitely see the red spot, festoons and transit shadows with a 5"+ scope even when it's low - They're only about 130 quid which isn't peanuts, but in the world of astronomy kit it's at the lower end! :)
  13. I had that concern too, but ended up using windows that were only 150mm wide so it's impossible to get in through them. You could always have a curtain or shutter to stop anyone looking in. Personally, I'm really glad I put windows in because a bit of natural daylight in there makes working on the scope much easier and more pleasant. I open the roof too if possible but more often than not, it's raining!
  14. I have a 12 mm supermonocentric that's very nice on planets but with my scope's relatively short focal length (1250mm) it needs to be coupled with the 1.8 barlow to give something more useful magnification wise. I actually find the 12mm and 1.8 barlow preferable to use than the native 6mm mono just because the eye relief is better. UO orthos are also very nice EPs on planets and the moon and were (when they were available) vastly cheaper than the monocentrics!
  15. What a superb job you're making of that! looking forward to seeing the finished scope
  16. 2.4m should be fine I think. Mine's 2.3 and it's plenty big enough for visual observing and maintenance of the scope. Octagon with a dome would probably look quite nice too!
  17. Victorian aesthetic of course! But practical too. The fold down box sides provide space for temporary storage of eyepieces and filters as they're being swapped in and out of the telescope. The 1.25" tray is removable and underneath are a few more bits and pieces that get used far less often. I used to keep eyepieces in the telescope pier but once the pier was permanently outside in my observatory I found they were getting dusty so decided to make a traditional eyepiece case. Now they can all be kept inside but be taken out when needed either in the obys or with my portable scope
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