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MimasDeathStar

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About MimasDeathStar

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  1. You may want to reconsider your setup. You will have several challenges to overcome: The 76 eq has a spherical not parabolic mirror which means that you are going to struggle with focus either way - and probably have some fuzziness at the edges even if you can get the centre in focus. The 76eq wont reach focus with a camera as the focusser doesnt have enough inward travel to reach focus. You have discovered this - and that is why you have managed to get around it with your barlow and eyepiece. However... The longer the focal length the more difficult it is to track. On top of this, you need much longer exposures than you would with a short focal length. You now have a focal length of 2.1metres - ignoring the 15mm eyepiece. This is absolutely gargantuan! The star adventurer is not comfortable with focal lengths above 300mm or so. So you see your problem Additionally the long tube of the 76eq will make balancing your setup on a star adventurer a challenge due to the long tube length. The only possible advice I can give you is to totally abandon the idea of using this scope for astrophotography. You will achieve exponentially better results just using your dslr on your star adventurer with lenses up to about 300mm. edit: you would have to physically shorten your scope tube to achieve focus with a dslr
  2. I see. I suppose a rep may be trying to rationalise a nebulous concept so I can see where they are coming from. But I don't agree. Imagine a scenario where you could get every major eyepiece on the market and test them against these known standards, and then plot them on a chart using a quotient of some sort. Well in that scenario - picking your eyepiece would take 10 seconds and require almost no thought at all. It would be easier for eyepiece manufacturers, and consumers. But you have to factor in the subjectivity of eyepiece selection - which is based on many more things than just cost: It depends a fair amount on the telescope type, the aperture, the focal length. It depends on your favoured targets. It depends on your preferred field of view, and then it depends on how happy you are sacrificing edge sharpness for field of view It depends on your own eyes, your own hands, and how comfortable you are getting close to the eyepiece or whether you wear glasses Only then can you really compare eyepieces, and then it is so so subjective. I've got a 17mm Plossl that cost me about £20 - and I've got a 13mm Baader Hyperion that shows almost the exact same area of sky, but cost £100. In my scope there is very little difference between them. Certainly not a "5-8%" difference. But the hyperion has a wide field of view, slightly better edge sharpness, slightly less light fall off on the edge, a much nicer exit pupil. But it is much heavier. But its also 5x more expensive. Zoom's are great eyepieces and many people own one (me too), but its not as if they are some well-kept secret. If what the rep was saying were true then very few people would own anything but zoom eyepieces and that's just not the case.
  3. Where did you get the "5-8%" figure from, I've never heard of eyepieces being quantified on any sort of ranking scale before, short of using a ronchi test I have no idea how it would be possible to make such a statement? Its not really possible to say eyepiece X is 43.7% or whatever better than Y. Like you say, its all subjective. Its only through trial and error that you can make a decision yourself what is an appropriate amount of money to spend on eyepieces. Just a word of warning though - as I'm sure you will find out in due course - nearly all astronomy items always (and I mean always!) get at least 4 out of 5 stars! And zooms field of view goes backwards - so it would be 40 degrees at 24mm and then 60 at 8mm (it might not sound it but it is a whopping difference between 40 and 60% at 24mm). Most zooms do need refocussing ever so slightly. The largest drawback with zoom eyepieces is their narrow field of view. But like you say - there is no eyepiece (zoom or otherwise) that will either A: completely transform your experience at the telescope or B: show you much more or create a transformational experience in terms of sharpness or definition, its worth keeping that in mind if you are feeling overwhelmed. If Saturn is not completely sharp at 60x in your scope already with your 25mm eyepiece it is almost definitely one of two things - atmospheric conditions (Its really hot, and Saturn is really low, so it'll wobble about in the haze no matter what) OR your scope is out of adjustment. Of the two it is 99% more likely its just the current atmospheric conditions. A £50,000 eyepiece couldn't make it any sharper. But either way, a zoom is a reasonable choice and very versatile.
  4. That is about the most that you can extract in terms of an image with your current equipment. I think it is a very good picture, nice and sharp and looks in focus. The big problem is that the sun is a bit boring now and just an orange ball! Pictures will look more exciting when there are some sun spots. Filters probably wont make a significant difference.
  5. Message about 12" / 10" incoming!
  6. I'm no telescope expert - but is this a new telescope? http://www.opticalvision.co.uk/astronomical_telescopes-sky-watcher-dobsonians/heritage-150p-flextube.html It looks like a new skywatcher telescope to me although I couldn't find much information on it anywhere. It looks pretty cool to me, and a nice step up from the 130p.
  7. Don't worry about it glad you are sorted. If it helps I have done the exact same thing more than once (and much worse)!
  8. They can be a bit fiddly at first. The easiest way is to take your finderscope (pedantic - you have a Red Dot Finder - RDF - not a finderscope ) off the telescope to test. Adjust all of the adjustment knobs so that they are about halfway through their range of motion. Take the finder scope to a relatively dark / dimly lit place (doesnt have to be pitch black) - and then switch on. Turn the knob all the way round to full power and make sure the little LED is illuminated. Hopefully with it now just in your hands you can wiggle it around and then eventually you'll be able to close in on the red dot on the screen. You have to remember that it aligns with the line of the telescope tube so it can actually be quite tricky and require a wee bit of contortion to get your eye in the right place the first couple of times. But once you;ve found it then it should be easier to know where to put your head/eye when on the scope. And then you can adjust it to a bright star point. NB - a light will only show on one side of the screen (eg the side facing the led) I only say that in case you have tried turning it round to line it up and look straight through - cos it wont work... Best of luck.
  9. I'm really sorry if this sounds like I'm hijacking your thread - but... is that the lens that came with the camera or is that a difference lens? I'm thinking about buying one of these cameras you see! Great shots btw really pleased you fixed the picture issue. These all sky projects look amazing fun but I think they may be a touch too technical for me!
  10. Thankyou for the advice! I read those articles and I must admit I have a bit of a headache now but I think it looks like the 224 makes more sense for my scope than the 290 so that's good news especially as it is the cheaper of the two!
  11. Hello everybody I hope you don't mind me asking another dreadfully naïve beginners question (a noob question so my kids tell me!) but I was thinking about getting a solar system camera and for the life of me I cant work out what the difference between these two cameras are! Armed with nothing more than the "they're more expensive than the ASI120 so they must be better" level of knowledge; I've quickly run out of steam. I really really like the look of the ASI178 but I think it may be too expensive at the moment. I've googled and read various forums about this very topic a few times and I must admit the debate quickly reaches a point where my brain takes off its reading glasses and goes off to sit in a quiet corner... I think I understand the basic selling points - resolution, quantum efficiency, pixel size, and working out sampling size and so on but these units seem so very close in so many respects that I cant help but wonder why they both exist? Superficially they seem so similar, and I'm really relieved that I'm not the only person confused by this (as I've seen so many people ask a similar question!). I'm guessing they both must have their own USP but I haven't figured out what that is. And I thought I knew about photography before I bought a telescope! Ofcourse underpinning all of this is a fundamental lack of knowledge and a broad spectrum ineptitude at anything above basic GCSE knowledge so I'm sure someone can point out why I'm being so daft! Thankyou! BTW my telescope is a Meade Polaris 90mm refractor (900mm focal length) an a basic EQ mount, I was just hoping for something as "all round" as possible - sun / moon / planets and so on.
  12. No I'll have a look at that thankyou for the advice!
  13. I'm just using a baader solar film filter. You think a wedge would make a big difference?
  14. Hello all, I was thinking about white light solar imaging but I am a little confused as to what would be the preferred technique. With my little scope I'm a bit limited to full disc shots as I'm not picking up a huge amount of surface details (espescially with it being solar minimum I guess!). I think some people are just using a dslr and taking shots and prime focus - whereas others seem to be using lucky imaging of the full disc - or lucky imaging to build up mosaics. Is there a "best way" to do it? I would have assumed that the mosaic shots would hold the most interesting details but the full disk dslr shots look pretty great too to me so I'm not too sure! Many thanks
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