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spike95609

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About spike95609

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  1. If the secondary is centred in the focuser but you can't see the mirror clips then yes it's out of alignment. Slacken off each of the three little screws on the secondary a bit and then move them around until you can see the clips spaced evenly around the edge of your view. This will confirm that the secondary is angled with the focuser to look straight down the tube at the primary. When tightening the secondary screws back up, do each screw a fraction of a turn at a time until all of them are tight, otherwise you'll knock it out of position again. After that it's just a case of moving the primary around until you have the dot inside the circle.
  2. First slacken off the three screws around the secondary a little, otherwise you won't be able to turn the centre screw at all. When you turn the centre screw the secondary mirror should move fairly quickly up and down the tube. Just adjust it until it looks centred with the focuser, i.e. the gap between the mirror and the edge of the focuser is equal on both sides. Then with your cheshire, make small adjustments to each of the little screws until you can see all of the mirror clips holding the primary mirror (there may be 3 or more of them depending how large your scope is) spaced equally around the edge of your view. The best way to think of these screws is as a three-way balancing act, propping up the mirror, so when you tighten them up don't do each one tight in turn or you'll knock everything out of alignment again. Just turn each one a fraction of a turn at a time until they all become tight, and you should still be able to see the primary mirror clips spaced equally about. Then it's just a case of using your cheshire to get the dot in the middle of the circle.
  3. There's no other sensible way to lift it in one piece without holding on to the handles. They are fairly solid though as there's a 10mm thick steel bar inside them which screws into the base. That said the metal component of it stops I reckon about 10mm along the length of the plastic handle, which isn't much of a problem because a lot of the weight will be resting on your index fingers and the metal will be under them at that point and therefore supported. Although I think the possibility of a stress failure in the plastic is pretty low, and as the bar is so short I think you'd have to apply pretty extreme pressures to it to risk a fracture, I would still only really want to rely on the handles for short hops now and again, relocating the scope from one position to another, rather than carrying it that way all the time.
  4. I've just measured it and it's a little bit wider, 53cm I make it.
  5. Speaking as a 250px owner, it's a terrific scope, and hits a great balance between price, power and portability. I've never used a flextube dob, but I wouldn't think there's any difference in optical quality, it should be the same mirror surely? I went for the solid tube because space wasn't an issue, and naturally there's no messing around with shrouds or worrying if extending the tube has an impact on collimation or not. I check the collimation now and again, and as I just take it into the back garden so it never gets bounced around in a car, I haven't had to adjust it once since I bought it 4 years ago. The solid tube is also lighter than the flextube, and even though it is pretty chunky, if you have an average amount of strength about you it's not a problem to lift it around. I lifted it in one piece from one end of the garden to the other a couple of nights ago, weight isn't so much of a problem as sheer bulk in that instance as it keeps hitting your legs as you walk. But doing it the sensible way and carrying it in two pieces it's perfectly fine. I'm 5' 9" and don't have any problems with the height of the scope other than bending knees. Even when pointing vertically, it's bang on 4 feet from the floor to the eyepiece, so the shorter you are the better I'd guess. As for collimation, when I was deciding whether to buy the 250px or the 200p I got very worked up about collimation and imagined it would be a lot harder. As it turned out, the basic process is the same for any dob, and as I said I've only had to do it once. Make sure the spider vanes are equal (mine were), then move the secondary up or down the tube until it's level with the focuser, then adjust the secondary until you can see all the mirror clips on the primary spaced equally around the edge, and finally get the dot into the centre circle of the primary. If you've never done it before it sounds rather complicated, but take each process one at a time and understand what you're doing and it's quite simple really. Providing you're comfortable with the weight (not that an 8" is all that much lighter), you'll enjoy this scope and may not want another. My skies aren't awful with light pollution but they're certainly far from brilliant, nevertheless I've managed to glimpse about 150 galaxies with this thing so far, which is much more than I thought it would do. I don't feel the urge to upgrade to something bigger. Sure a 12-16" would show more, but it also starts to cost a lot more, weigh significantly more, and carrying it between doorways and over tables like I have to becomes a problem. If I had to move something like that about, I'd probably talk myself out of using it and decide I wanted to watch TV instead, whereas I can comfortably set up my 10" outside in a couple of minutes and still marvel at what it shows me.
  6. I haven't had the opportunity to look through any other high end binoculars, but the original Swarovski EL 10x42s were something to behold. When I was testing it against my Vanguard Endeavor's, I found that sharpness is really the wrong term as you can get any decent pair of binoculars to get a sharp focus. What it really comes down to is resolution, and as they were 5x the price the grind on the Swarovski lenses naturally goes further and much more fine detail leaps out at you. It's a subtle but noticeable thing. It took me time to figure out what it was; looking at the moon they were both sharp but I just had the idea that the Swarovski's were revealing more. In daylight I realised it was the resolution when I started looking at saw dust that insects had dug out of a dead tree some 15 yards away; with something so small and fine you could clearly see the higher quality lenses were dragging out more fine detail; even though the overall image seemed pretty much identical at a glance. Is it worth £2,000? If you are happy to throw that much money at it then yes, if not then you'll be completely happy with something less.
  7. Very pleased to say that I got 46p last night. I managed to get out in the early evening before the moon came up, and it was reasonably easy to find at the top of Auriga. It didn't appear wonderfully bright in the scope but obvious enough with direct vision at 38x. I had a go with my 10x42s and was very surprised that it stood out fairly well as a faint smudge in them. I then went and tried my 15x70s for comparisons sake, but by this time the moon was coming up and it started to get washed out. First comet I've seen for nearly two years!
  8. I started off using a pair of binoculars and the Sky and Telescope Atlas. You're limited in what you can see with binoculars of course, but the wide field of view will make it harder to get lost, and with some decent glass you should be able to detect many of the brighter DSOs in the sky. Another advantage of binoculars is that everything is the right way up, looking through a telescope the world is upside down and back to front - not the easiest way the learn star hopping. Also you could try restricting yourself to just a couple of constellations in the same area of the sky per session, that way you can to memorise what the constellation looks like so you'll know it next time. Jumping around from one part of the sky to the other might end up confusing you.
  9. I shouldn't think you'd be disappointed with the 200p, it's cheap, simple to use, and even under light polluted skies has enough power to start venturing into the difficult to see stuff, like deep sky objects. Plenty of people find that it's all they ever want from a scope. As to accessories, I agree that it's best to see how you get on with the basic kit before throwing any money at it. What you are given is enough to get you going, and over a few sessions you'll start to figure out what may be lacking, and what new eyepieces you need to plug the gaps. This way you can make an informed (and economical) decision about what you need. There was lots that I was sure I'd need when I first started, but after 4 years all I really ended up getting was a couple of filters to bring out nebulae (don't use them very much), and while the four eyepieces I've got nicely cover the range of pretty much anything I'd want, really it's the 32mm and the 10mm that get by far the most use.
  10. I'm not surprised they cancelled the Overwhelmingly Large Telescope because no matter how large a telescope is, someone can always make a bigger one, and in terms of adjectives where the hell can you go from there?
  11. I think it all depends on what you'd like your telescope to achieve. A 6" will give you nice views of the planets, the moon, and some of the brighter deep sky objects like galaxies, nebulae and star clusters. This is generally considered the ideal scope for someone who is just starting out and would like to know if this is the hobby for them without having to spend too much. If you think you're likely to develop an interest in deep sky objects, then the more aperture the better as these things are very faint and you need the extra inches to tease them out. Going down this road starts to become a balancing act between how much power you would like, how much you're prepared to spend, and how much you can physically lift, as the larger you go the cost and weight dramatically accelerates. I went for the 10" as it's a very nice balance between all three. If you intend to make this a hobby for the long term though, I'd recommend stretching just a little bit further to get an 8" scope as it doesn't cost all that much more, and its significant amount of extra light gathering power means that it could well be the only telescope you'll ever want.
  12. The 150p is an excellent scope to be starting out with, I'm sure you won't be disappointed. If it were me I'd prefer to buy a collimator at the same time as the mirrors are almost certain to need a bit of tweaking to get the best out of the scope, but there's no reason to break the bank by going down the laser route, a simple cheshire collimator eyepiece and a collimation cap are all you need. After that though I'd recommend that you not buy anything else until you've had the chance to get a feel for the scope. The finder scope and the eyepieces that come with it will be more than enough to get you going. After a few sessions of looking at all sorts of different objects in the sky, you'll start to get an idea of whether you'd prefer an eyepiece with a wider view, and if you think you'd benefit from a little more or less magnification.
  13. If deep sky objects are your thing, the more aperture the better. I went for a 10" because it seemed to me to offer a perfect balance between performance, portability and price. An 8" wouldn't show as much, and a 12" for the Skywatcher scopes I was looking at was a lot more expensive and starts to become more cumbersome. The difference in viewing between an 8 and 10" is not huge at all. It just means that the 10" will see very faint objects that the 8" can't quite get, and those which are faint in the 8" will be a bit brighter in the 10, and everything will have just that little bit more detail. My skies are about the same as yours and I've managed to see about 120 galaxies with the 10", I'm not sure I'd be even close to that with an 8".
  14. When I bought my Vanguard Endeavor II 10x42s I had a very very close look at the Vortex Viper, and couldn't really decide between them as they were so closely matched. Ultimately it came down to the cost, and the Vanguard's are a lot cheaper in the UK than the Viper's. I've been extremely impressed by how much those relatively small lenses can pick up in the night sky, and I'd imagine your binoculars will match them. The Vipers are an excellent piece of kit, with quality optics, ED glass, very high light transmission, and a true aperture of 42mm unlike cheaper models which say 42mm but are actually somewhat less. "Astronomical binocular" really just means a normal binocular with very large lenses. Nominally a 50mm aperture would show you more, but with the quality of your lenses and the coatings on them I doubt you'd see any improvement unless you bought a 50mm of equivalent quality. Then there's 70, 80 and 100mm apertures, and they will certainly show a lot more, but this gets us into the realms of handshake and the need for tripods. These big binoculars have many benefits but come with a degree of inconvenience which you'll never have with a simple and pretty powerful pair of 8x42s in your pocket.
  15. I've been very happy with my 6 and 10mm, very sharp, comfortable to look through, and with enough contrast to draw out those extremely faint galaxies. I use the 10mm on pretty much everything as it hits that sweet spot of providing enough magnification and contrast to see the small fuzzies, but not so much that the atmosphere washes it out. When I bought my TV Plossls they were a lot cheaper and the SLVs more expensive than they are now, but if I was doing it all over again I'd probably end up with just a set of SLVs. The 15mm plossl is comfortable enough and certainly good enough that I can't justify replacing it, and I might never add another eyepiece to the collection, though I do occasionally think about throwing the 25 and 5mm SLVs in there for a bit more flexibility.
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