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NGC 1502

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Everything posted by NGC 1502

  1. Not knocking Orion Optics but Asian mirrors are generally very good. Most of the time telescope views are limited by the quality of the atmosphere we look through. The rare occasions that we enjoy steady skies is when premium optics may pull ahead with objects like planets and double stars. For the faint fuzzies, galaxies and nebulae then optical quality is not crucial. As always, your mileage may vary…..
  2. Good point, and would have been easy to sort that at the design stage.
  3. I have an original version Vixen LV 2.5mm. It gets used with my ED80 to give a very high 240x for splitting tight doubles. Too high for most objects but brilliant at what I use it for. The later versions like the SLV addresses the only criticism I have of the original LVs, that’s the roll down rubber eyecup, rather than the better screw down. Ed.
  4. Brilliant scope, fully understood why you like it so much When you’re able to have a longer session at a dark site one thing to beware of is the dewing up of the mirrors, especially the exposed secondary. A couple of ways to combat the dewing- An electric dew gun (portable hair drier), a shroud around the extending part of the tube. Enjoy the great views and maybe let us know what you saw Cheers from across the pond, Ed.
  5. The Teflon bearings on earlier OO UK Dob mounts had a habit of coming adrift. That’s happened on both of mine. They are formed from flat Teflon strips forced into the curved cutouts in the aluminium mount, so the flat Teflon takes on the curved shape. If the Teflon strip is fractionally too short it’s not quite tight enough and with use can slide out. It might be possible to wedge it in place by forcing it back in with a packing piece on the end, effectively making the strip a fraction longer. Trial and error needed to be effective. The problem was fixed on later mounts with a completely different shaped cutout in the aluminium mount. The original cutout in the aluminium was curved in the same direction as the altitude bearings. The updated cutout is curved in the opposite direction, that maybe counterintuitive but actually is much more secure.
  6. If you shift the teflon pads higher up the curve this will increase the resistance. Trial and error should sort it.
  7. Either term is appropriate, some call it a “chrome barrel” but of course some barrels are black anodised.
  8. Although I’ve never owned an SCT the second post does say “effective” aperture. I’ll be back later to see what others have to say. An interesting thread…. Ed.
  9. Apologies because my opening post wasn’t clear. My 10” will spilt Alnitak but not at every attempt, needs reasonable seeing plus of course at as high an elevation as possible. For those not familiar with Alnitak there’s a faint field star much further away that could perhaps confuse observers. Alnitak’s secondary is tight in to the primary, my double star atlas says the separation is 2.4 arcsec which is not all that close, it’s the magnitude difference that’s the problem, as previously mentioned. The above was my first try with the ED80 and I was surprised to succeed. Of course I’m not trying to say an ED80 will do everything as well as a 10”. Both scopes are “better” than the other according to what’s asked of it. Ed.
  10. Excellent topic Looking at the list you mentioned you’ve included one of my favourite coloured doubles, Iota Cancri. During a recent late night session I observed it rising in the east with my ED80. This wide coloured double was an easy split at 22x in my ED80, but the colours were more apparent at 50x.
  11. During a recent unexpected late night clear slot I was out with my ED80. I’ve often found Alnitak (easternmost star in Orion’s belt) quite tough to split in my 10” Dob. The 10” is excellent quality and is kept well collimated and fully cooled before attempting anything difficult. During that recent ED80 session I was enjoying lots. Then I thought I’d try to split Alnitak, not expecting to succeed. At 120x I thought I could detect the secondary. Going to 240x the split was confirmed, intermittently but clearly in moments of half decent seeing. Just wondering about other visual observers experiences?
  12. A simple question hopefully- Is a regular 12v flexible dew band polarity sensitive? Thanks, Ed.
  13. On Monday evening 1st November a few local club members and myself were at one of our club’s dark sites. It’s not a true dark site but it’s very definitely better than in town, and has excellent horizons. I decided to take my ED80 refractor that had been returned to me recently, a friend had been using it. He’d upgraded to an 80mm triplet for imaging, therefore he returned my SW ED80 doublet. On arrival at our venue the sky was wonderfully transparent, the MW easily seen. With Cygnus overhead I fitted my Ultrablock filter to my 27mm eyepiece to give 22x and a 3 degree field. First up was the eastern Veil, no problem at all to see. A pleasant surprise was also seeing the dimmer western Veil just crammed into the 3 degree field. An even nicer surprise was NGC7000, the “Gulf of Mexico” part readily identified, but mirror reversed with the necessary diagonal. M27 was almost shockingly bright in comparison, so I tried for the “Little Dumbbell” M76. It is of course a very short star hop from Phi Persei. I could not spot M76. I panned around…..and then the penny dropped….being more used to Newtonians I’d temporarily forgotten the east-west reversed view I was using. My target slid into view when I panned my alt-az mount correctly. The elongated dim hazy spot was better seen at 50x. With filter removed I tried for some old favourite often observed galaxies. M31 had an obvious bright core contained in an approximate 2 degree elongated haze, M32 & 110 all together in the 3 degree field. Of course M81/82 but they’ll be much better placed in the spring. Another pleasant surprise was the easy visibility of M33. Now this is hardly ground breaking observing but somehow much more satisfying when using a very modest aperture. I just love the simplicity of the kit I was using. Lots else followed but by mid evening the sky deteriorated and dewing up became an issue so we headed off home after a pleasant time. Ed (not Ting)
  14. Last week my Skywatcher ED80 was returned to me after being on loan to a friend for 3 years. I’ve had two sessions since its return, on one of those the seeing was intermittently steady for several seconds at a time. To split Delta Cyg is described as difficult with a 3 or 4 inch scope in Burnham’s volume 2 page 758. Of course that does depend on the separation listed as 2.5 arc-sec in the Cambridge Double Star Atlas 2nd edition. The 2.5” separation was from 2013, and as the orbital period is estimated at 918 years that separation will have hardly changed by 2021. During the previously mentioned session, with Delta Cyg overhead I was delighted with a clear split at 240x. Of course that’s very high power for an 80mm scope, achieved with my 2.5mm Vixen LV. But I’ve found like many others that double stars can take very high power above theoretical limits. I’d be pleased to hear of similar observations, especially if success was achieved with an aperture smaller than 80mm. Ed.
  15. Unfortunately I don’t think any anti-dew measures can be 100% effective. It’s a case of doing the best we can and hoping we keep the dew away for as long as possible, as you’ve already suggested. For SCTs a long dew shield plus a low heat band around the corrector plate, and perhaps the occasional use of a 12v low heat gun may be successful in giving you long enough to enjoy a good session. Possibly others may have further or better ways of helping this issue, so I’ll check back later to maybe learn something.
  16. As above….plus Rigel Quikfinders when viewed in daylight are very dim even when at max. Also it’s crucial to have your eye in the correct place to see the illuminated rings. Try in dim or night conditions, and move your eye around. At night the Rigel is excellent. Many red dot finders don’t go dim enough for nighttime use, the Rigel does, top bit of kit. Ed.
  17. As long as the movements are very smooth (which I fully expect they will be) I can easily live without slow motions. I once had an Astrotech Voyager alt-az with slow motions. It does depend on the length of the scope but even with a 900mm focal length refractor I found stretching for the slo-mo controls was a pain. I tried longer cables but it was still a pain. It was far easier to hand guide by holding the focuser because that’s always in a convenient place. The other issue was the AT Voyager dovetail clamp was on the end of an arm. I found that a Giro type mount with the weight of the scope closer to the mount head was noticeably more stable, so I think I’d prefer the similarity with the AZ 100 & 75. YMMV of course…. Ed.
  18. I have some BST Starguiders bought new a few months ago. The rubber eyecup just pulls off. To do that it doesn’t need to be screwed up or down, eyecup pulls off at any position. So why did I pull eyecups off new eyepieces with no issues? Dunno…is the honest answer….. Ed.
  19. Some observers use an accessory called a “Monk’s Hood”. Basically it extends beyond the face to help block ambient light. I often use a balaclava helmet that has a floppy face opening that does the same thing. Keeps my head warm at the same time. One issue that can occur in cold damp weather is restricted air flow around the eyepiece can cause it to fog up. But the basic idea of blocking ambient light can be a simple way to make the view more contrasty. Ed.
  20. The previous post does highlight the frustration of dodgy forecasts and I certainly understand that. I arrange visits to one of my local club’s dark sites and it’s myself who’s usually responsible to confirm or cancel the scheduled event. Often it’s a tough call. But when it all comes together it’s great to be together under a good sky and makes up for all the hassle. Observing on my own is far different, it’s then I can relax without the further frustration of all the hi-tech equipment that just gets in the way of enjoying the night sky. I echo 100% previous comments. Ed.
  21. +1 for this. The following morning when the scope will be at inside temp uncap everything as above, no new moisture will form. Allow to thoroughly dry out, cap and safely store.
  22. Good advice already given. I’d like to add the following for observers in the northern hemisphere. In any scope without a drive, if you watch where stars drift OUT of the field of view, that’s WEST. If you nudge the scope towards Polaris, watch where stars ENTER the field of view, that’s NORTH. Ed.
  23. There’s no doubt that a good 4” refractor gives lovely views with stars as tight points of light. But if you want to see globular clusters looking like a ball of stars rather than a fuzzy patch then a larger reflector gets the job done at a fraction of the price. The old “horses for courses” applies. Ed.
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