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cloudsweeper

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About cloudsweeper

  • Rank
    Sub Dwarf

Profile Information

  • Gender
    Male
  • Interests
    Physics, maths, history (family, military, social), pre-modern architecture.
  • Location
    Merseyside, England
  1. Manual or Goto?

    DON'T DO IT. Keep away from the Dark Side. Maintain a high pleasure-to-hassle ratio! *ducks behind parapet* Doug.
  2. Fed up

    .... or a non-driven frac! Up and running in no time, no alignment, no collimation, use immediately (although a bit of time might be of benefit), widefield for finding your way, and dead easy to swing all over the place and get to clear areas. Only 100% cloud stops me! Doug.
  3. Signed up to an Astronomical Society

    Good move Neil! The Liverpool Group is too distant for me, although I did enjoy a demo evening of theirs a couple of years ago, a bit nearer home. Doug.
  4. Well I knew the Universe contains more stars than grains of sand on Earth, which in itself is startling. I mean, even just a handful of sand seems like an enormous amount of grains. But according to this source (see link), if you want really small, consider that about 10 drops of water contain roughly as many molecules as there are stars! That I didn't know, and it has got me eager to obtain Blatner's upcoming book. http://www.npr.org/sections/krulwich/2012/09/17/161096233/which-is-greater-the-number-of-sand-grains-on-earth-or-stars-in-the-sky Doug. Edit: This is an old link. The book is already available. I'm about to order a copy.
  5. Or even - Not Another Orion Post! Over recent mornings, Orion has been in the south before 7am, and too faint to merit setting everything up. So when it was clear at about 3am this morning, I took advantage and put the ST120 into action. Nothing ground-breaking - just a pleasure to revisit an old favourite. M42 was first, at x14 and x20 - clearer with the UHC filter, and more so with the OIII, although stars were dimmed more with that one. At x60 the Trapezium sprang into view. Still only four stars seen at x150 - seeing and transparency not great. But a new observation for me was to take a look at Cr (Collinder) 70 in its entirety. It's an open cluster of about 130 stars spanning around three degrees, so the 42mm Revelation (giving 4.55 deg) framed it nicely, showing Mintaka, Alnilam, and Alnitak (the three stars of Orion's Belt) in a rich starfield. It was a pleasure to absorb the view and appreciate the benefit of a widefield 'scope! Thickening cloud prevented further exploration, but these easy and common observations constituted a very enjoyable 90 minutes. Thanks for reading. Doug.
  6. Help with stellarium?

    With my 'scopes I use CTRL ^ H to make the display the same as what I see in the eyepiece. (Lateral inversion.) With a reflector, you should use CTRL ^ V to do the same thing - it rotates the view by 180deg. Doug.
  7. 1.25 inch, 58 degrees, 16mm eye relief, five element modified Plossl, FMC, rubber eyecup. Very good condition, no faults or damage. Price: £24.00 plus £3.00 UK P&P, payable by Paypal as a gift, thanks. Doug.
  8. I bought the now-discontinued Radian to replace the S/W when I spotted it on an auction site. The TV has seven elements, 20mm eye relief, and 60deg of AFOV, while the S/W has respectively five, 16mm, and 58deg. The TV's eye lens is slightly larger, and its rubber eyecup is in an adjustable clickstop housing which I have not encountered before. In the ST120, these EPs give x100 at 0.60 and 0.58deg of TFOV. Nine days ago I compared the two using the waxing gibbous Moon, putting the terminator right across the centre of the FOV, and almost reaching the edge of field. The Radian showed sharp detail right to the edges, while the S/W gave a very slight loss of sharpness there. Targeting a crater in centre-field, the fine detail appeared slightly sharper with the TV. (Or did I just want it to?!) And so to the present - looking out at 1.30am the sky was very clear, so I set the ST120 up again and got M45 in view. Before using the 6mm EPs, I admired the cluster at x14/4.55deg. It is truly beautiful when seen in its entirety like that, a spectacle the long FL 'scopes can't match. M45 looked somewhat sharper in general, and right to the edges of view with the Radian. The stars looked a little brighter somehow, which I would put down to better contrast. While my comparisons have not exactly been exhaustive, I reckon I can safely say that the Radian is the better EP, which is of course to be expected, but the differences are subtle rather than dramatic. As a further conclusion, the S/W Planetary is a perfectly good EP, and unless an EP gives a really poor view, upgrading is perhaps a luxury rather than a necessity, and might be best reserved to improve properties such as eye relief and AFOV. Doug.
  9. Fed up

    Cloudy conditions are indeed a pain. But they won't make me lose interest. Just more excited about the next time out! Doug.
  10. Eye Pieces you would like to try out

    Easy. I want the imaginary TV 56/82 to get a decent FOV out of my 8SE. Plus LER, 500g max, and for under 200 quid. Know any smart designers?? Doug
  11. Zero-Cost Observing Hood

    I was looking at a thread here recently which mentioned the r-sky.org hood - about £27 I think - which is an excellent item for the job of blocking stray light and increasing contrast. But I wondered if I could come up with something similar for less money. In fact, no money at all. The problem with draping a towel or T-shirt over your head is that they hang too close, so condensation ruins everything very quickly. I needed a way to keep the old black T-shirt away from my face. A plastic handle off an old bucket is ideal. I used a rectangular-shaped one, but a semi-circular one would be as good. I placed it inside the neck and shoulders of the shirt, and held it there by drilling a small hole in it through which it is fastened to the neck-loop with a twisty tie. Nothing else - this allows the sides to fall downwards in use. Finally, a small bulldog clip holds the tops of the sleeves together under the chin. It works a treat, and can easily be adjusted forwards and backwards, since the weight of the back of the shirt keeps it on your head by friction. Nothing is permanently fixed, so the shirt can simply be released for washing. Doug.
  12. 8/10/17 report

    Nice report! Concerning being a father, I've just spent a nice weekend visiting my daughter to mark her birthday. (Quite a bit more than her 13th!!) Doug.
  13. What reduces chromatic aberration?

    Stop down the aperture and it's gone - OK for bright objects. Doug.
  14. 2 eyepieces plus barlow = all I need ?

    OK, it is easy to get carried away. I'm three years "in", and have 15 EPs and a zoom. (Once had a Barlow, but would rather have a set of EPs than extra glass.) So I've got a good range of mags and exit pupils covered, but then there is FOV fever, slightly less addictive than aperture fever, but enough to set up a "wanted" list. Anyway, as a result of this thread, I've had a good look at which EPs I use frequently, and as a result, have concluded that the WA replacements I thought I wanted are no longer necessary. Great! Lots of £££ saved, and deep satisfaction with what I've got. Thanks everyone! Doug. (But I still want further 'scopes.....)
  15. Crème de la crème.

    Dead right, Alan - I started out with just a 70mm frac, and had great views of M42, M45, Mizar/Alcor, Moon, Venus (crescent), Jupiter and moons, and even sunspots (with suitable protection of course). I thought the sunspots looked like strands of frogspawn - another "wow"! Doug.
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