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Ruud

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About Ruud

  • Rank
    Free-Floating Planet

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  • Gender
    Male
  • Interests
    Thank you for visiting my profile. Besides astronomy, I take an interest in photography, skepticism, science, maths, podcasts, radio and cycling. I teach mathematics.
  • Location
    the Netherlands
  1. I hope you'll be really happy with the new eyepiece! I love low magnifications myself, and the Maxvisions happen to be top class eyepieces. About their history: JOC (Kunming, China) made Meade's eyepieces. Meade broke up with JOC after JOC set up Explore Scientific to compete with them. When this happened JOC was in the middle of the production of a large batch of Meade series 5000 SWA eyepieces. Meade no longer wanted them and JOC dumped them on the European market branded as Maxvision, a brand they had used before. This cost Meade a fine, which was settled by Sunny who now is the owner of Meade. Meade uses a new manufacturer, United Optics, also in China. The Maxvisions are identical to the Meades, except for the name on the barrel, and where the Meades had a coloured ring, the Maxvisions don't. But there was a huge difference in price! I never bought the 40mm because I was intimidated by its size, and eye relief of the 16mm is too short for me (I suffer from long eye lashes). Optically, the ES 68° appear identical to the Meade SWA and Maxvision 68°. All three or on a par with Televue's Panoptics. The rubber eye cup is truly big, but I really like it because it is so effective. It creates a pitch black cavity with the view at he bottom. I do agree though, that these eyepieces look better uncloaked. Don, Starman over at cloudy nights, suggests a home-made eyecup made from a piece of bicycle inner tube as an alternative. See there for pictures.
  2. new

    Hello Leibek
  3. Helios LightQuest HR 16x80 binoculars have arrived!

    Looks so handsome, with those big eye lenses. Congrats!
  4. Copernicus and Eratosthenes

    It's a super image, Avani. very crisp with perfect contrast and tones. Excellent! And a nice mini lecture to accompany it. Couldn't be better. Many thanks for sharing.
  5. erect image diagonal

    The lower parts of the atmosphere are dense and turbulent with heat currents. This deteriorates the image when you look in a horizontal direction, limiting the magnifications you an use. Magnifications higher than about 70x are rarely useful in terrestrial viewing. Looking up and out of the atmosphere you look through less air and better air too. Magnifications over 150x are regularly feasible. Even a decent rectifying prism deteriorates the image, reducing the maximum useful magnification by a factor two or so, which means little for terrestrial viewing where the atmosphere is the limiting factor. But for astronomy the rectifying prism becomes the limiting factor, greatly reducing the highest useful magnification. The effects are diffraction spikes, loss of contrast and blur.
  6. Return of my 71. The Orion Nebula Ha

    A splendid image! (both versions)
  7. Binocular advice

    It's difficult to impossible to collimate binoculars, but there's a quick test to see if they are OK: http://www.nightskyinfo.com/binoculars-tests/ Binoculars are safe as long as you don't look at the Sun with them. Remember that the retina registers no pain and even at sunset, when the Sun looks dim in visual light, it's still too bright in infra-red light and unsafe to observe with binoculars.
  8. It's a beautiful image. A well composed and wonderful scene. The tones and colours are pleasantly balanced too. Very nice!
  9. Binocular advice

    In my experience poorly collimated binoculars either give double vision or an uncomfortable feeling (strain). Double vision can make you feel dizzy and the strain can cause a headache, but eye pain? An unsharp image in one or both eyes doesn't look good and causes no pain either. Could you tell us more about the pain you felt? Was it in both eyes, was it a stinging pain , a dull pain or what? When did you first feel the pain? Did you not forget to blink? If you are in Delhi, were you trying the binoculars during that really bad spell of air pollution that Delhi had a few weeks ago?
  10. Quickmap has recently been updated and now has a feature that lets you fly around any crater on the Moon while you enjoy a 3D view of it. This it how it works: Go to http://quickmap.lroc.asu.edu Select the Lunar Globe 3D projection and a texture that works around the whole globe: Find a place on the globe to view and start the 3D flight You should now see a 3D scene like this, spinning around the point where you clicked: To see the moving 3D scene you can use this link. It's a very long link, but it should get you there in one go: http://quickmap.lroc.asu.edu/?layers=NrBsFYBoAZIRnpEoAsjZwLpNKG%2BscB2fDbMADlPnNAE5rDgjZWakiE2mAmOuqt3J9%2BjTOKQ9QPRkmBSuBcgGZoPQUskVVYicDhwo3OQbRCkBkueCroisls5iLO63GX32%2B5cufe8bspWmt4M1urKMuEURFEhcChsDvIU9LoqPHEYcpGeWHqqymGkAHRQIKqJ6UiFZqXlNtDKRkoFTb7GFWrFrGUqTUkwfTVNntDDjZHU4%2BDiKtKyFaBjJTyzNaAd9fN1ves2ENN9bcoaezlNAdsjQUezBUS7iBVEW72G-TxP4x8ja0e-RpSAH7VQ8YLve4qIhXbIvFrJIJnLxBHooiiDJinPIqChZdFvdFPfLkRKYnKiaxgwlYtT4kkbCHPA6wlGgZG8GKY%2BZorEsPxBHE1WLVYAoL6LMU8QnjZSk-5JEpypDi1njOhzFXgGlyFDgemk8AIoZQkZwXkXaCs2nQYn9JoC6BOvz67laTZ%2BdSHaK4T2pDma4DgQyS4N2pDBplMYMBiPml08FZEcj6-HjZPu8MpUBR%2B0GkbQY0kzBAA&extent=-180%2C-90%2C180%2C90&camera=3447092.642252007%2C-740631.9919225845%2C-3332634.071787882%2C6.283185307179586%2C-1.5707963267948966%2C0&orbitPoint=-11.210365081203694%2C-43.63584717209528%2C3572.5823592720317&proj=22
  11. IC 63 Composite

    Its really beautiful!
  12. Sol HA WL 28-11-17

    Hi Charl, thanks for the images. I appreciate them, especially now that the Sun's really low in the sky and I barely get to see it at all.
  13. It's obviously very good! The framing is marvellous.
  14. Optical Wonder Baader Fluid

    Of course Baader Optical Wonder kills bacteria and fungi. Ethanol does that. Propanol too. I never used a lens pen and do not plan to. I prefer disposable materials for cleaning optics: cotton balls, Q-tips, solvent and tissues. The only non-disposable item in my cleaning kit is Giotto's rocket blower. --- Cotton balls ready to be disposed---
  15. Optical Wonder Baader Fluid

    Baader's optical wonder is a solution of propan-1-ol and alcohol. It's quite mild and will not easily remove a heavy grease. Here's a pdf on the composition: http://www.alpineastro.com/Reference_Docs/OW-SafetyDataSheet-P.pdf TV suggests acetone, which is MUCH stronger and can even dissolve some plastics. If the grease is thick and sticky you may have to resort to acetone, but first check with the manufacturer if the filter can be cleaned this way. I had something stick to my dielectric diagonal which would not come of with Baader's miraculously expensive liquid. It came of easily with acetone. I like Baader's because it comes in a practical spray bottle. For the rest it seems to have no advantage over alcohol.
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