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Posted by Paul A Brierley at 20:05 on 2010 Apr 14
OK I’m not that much of a beginner. But I am when using a Dobson mounted 10" and not GOTO!I was wondering if the dobsonian user’s amongst us, have any tips or advice for finding faint fuzzies with this kind of instrument?I will be using mostly a 24mm Panoptic and 35mm Ultima for wide field sweeping and then gradually increase magnification to see more detail. And on my telescope, I will have my trusty Telrad together with a 9×50 finder.I can use my laptop out side which has Skymap. But I also have SkyAtlas 2000, which I would prefer to use.So… Does anybody have any helpful advice for me please?Cheers
Posted by David Mottershead at 19:56 on 2010 Apr 15
Hello PaulI too use ‘GOTO’ scopes now, primarily because from the heavily light polluted site in Manchester that I observe from I really can’t see enough stars to star hop to all that I would want to see.However, when I first started out in astronomy I used undriven Alt Az and equatorial mounted scopes, and learnt how to navigate around the night sky and to star hop. Although having a laptop even back then, and having Skymap 2 (yes, it’s that long ago!!) on it, my prefered ‘weapons’ of choice were a northern hemisphere planishere and a copy of ‘Turn Left At Orion’. Armed with these I was able to succesfully navigate around the night sky and locate DSOs, doubles etc. As with anything, it really is a case of practise makes perfect, learning (or more likely in this case, relearning), the constellations and stars that make them up, and where, in relation to certain constellations/stars a given object is. I think I generally used to start with one or other of the main circumpolar constellations (as they are always visible to us here in the northern hemishpere), and then star hop across via other constellations to my target. The decsriptions and route paths provided in ‘Turn Left At orion’ were invaluable as well. So my advice, for what its worth, is refamiliarise yourself with the constellations and stars that make them up, draw up an evenings targets prior to your session, use a plainshere (doesn’t run out of batteries and let you down at a critical moment) and get a copy of ‘Turn Of Left At Orion’ as that, in conjunction with your planisphere and knowledge of the constellations, will provide a descriptive route to many worthwhile targets.Hope this is of some use.
Posted by Gary Poyner at 20:17 on 2010 Apr 15
Hi Paul,I’ve used Dobsonians for many years, and although I’ve been using a Meade 14 GPS for the past seven years, I’ll soon be returning to the joys of star hopping with a new 20 inch. I have been keeping my hand in with a 22cm dobbie as well though during this time.I observe variable stars – faint ones (CV’s to mag 16’ish) – from Birmingham. The best advice I can give is two-fold. Use the largest finder scope you can, and prepare your nights viewing with charts printed from one of the various planetarium software available. I use GUIDE 8, and would recommend this to anyone. It’s excellent for the faint fuzzies too. I would not recommend using a laptop – even in night mode – as this will affect your limiting magnitude. Just make sure you print the finder chart with the correct field orientation (Newtonian North to bottom, West to left), and remember that the stars drift towards the West. The finder is most important. 9×50 is OK, but a 10 or 12×60 is better. If you can get to mag 9 with your finder, you won’t have any trouble locating any object in the sky within a few minutes. Practice makes perfect of course, and after a short while you will be able to drop your scope on most fields without even looking. Good luck, and keep us posted as to how you get on.Gary
Posted by Paul A Brierley at 20:49 on 2010 Apr 15
Thank you both for taking you time to send me a reply.I agree with everything that has been said. And I will arm myself with a copy of Turn Left at Orion. Thanks for that David. I do have a very old copy of The Universe from your backyard, which I bought, when I bought my very first proper telescope; which, during that period was a 150mm (6") from Orion in 1991. I think that this book is also very good for visual star hopping. But I will look out, possibly for a second hand copy of TLAO.I think that I might have misled Gary, on the size of the finder. I think that it is in fact a 10×50 finder and not a 9×50. I will use printed charts from SMP10 and do as Gary has suggested, use these instead of the laptop. I think that for the first outing with the OD250S, I’ll practice star hopping, to the brighter messier objects visible during late Spring and early Summer. These are ones that I know, and know how to find. This way I’m sure, I’ll be able to learn my way around the sky, and begin finding the more fainter, and more challenging objects later.I like you Gary and you David, will still use my GOTO, with my SPX 200-800 f4. But I might do as Dale does.I have an Atik 16IC, and I’m thinking that it will be less stressful and perhaps more fun. If I take 60 second looped subs, and draw what I’m looking at. Instead of trying to image. Knowing full well how hard and difficult, that side of our hobby is!This is the beginning. If I am successful with star hopping, and I enjoy it. I have every intention of upgrading in four years time. To a bigger, Orion dobson. I’d like the OD350S De Lux; so whilst I’m outside using the OD250S. I can start saving for it. And If I’m lucky I hope that I’ll have this one when I am 50!!!
Posted by Callum Potter at 09:34 on 2010 Apr 16
Hi Paul,a couple of other suggestions.1. work out or preferably measure your field of views for your wide field eyepieces – then construct rings or make acetates for your Sky Atlas 2000. These can help when you narrow down to the vicinity of the object your looking for. You can do the same for your own printed maps, but try to print these out at the same scale.2. when out in the field with your atlas, orientate the atlas to the sky and try to ignore the ra and dec grid.3. make star-hopping notes, and take special notice of particularly coloured stars, or minor asterisms.4. i’d recommend Robert Garfinkles Star Hopping book. sorry that’s more than a couple :-)Successful hopping !Callum
Posted by Paul A Brierley at 17:41 on 2010 Apr 16
Thank you Callum,Your advice is very much appreciated.work out or preferably measure your field of views for your wide field eyepieces – then construct rings or make acetates for your Sky Atlas 2000. These can help when you narrow down to the vicinity of the object your looking for. You can do the same for your own printed maps, but try to print these out at the same scale.I have one of these already, so all I have to do now is work out the fov of my 24mm Panoptic and 10" f4.8
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