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Loopnova

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About Loopnova

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  1. Thank you for the link, that's precisely what I was imagining! Seems like a pretty uncommon solution and I'm beginning to realise why - even if it works, the downside is that the focuser will be obstructing some light inside the tube right? Maybe before I buy anything I will get the scope focused on a distant target and hold the camera as close as I can get to the focus extender to see what sort of result I can get. I'm willing to move the mirror but I wonder how this will affect my viewing ability with normal eyepieces? Is it possible to move both mirrors to preserve the 750mm focal length?
  2. I've been looking into attaching a Canon DSLR to a 150/750 scope. I know there are problems with achieving focus because the usual adapter that accepts 1.25" eyepieces puts the camera too far away from the focal point. It occured to me what if I were to cut out the middle man entirely and just attach the camera directly to the extending part of the focuser? Mine is threaded so I can unscrew the 1.25" adapter (see picture for the result of this). Surely there is a small t-ring that will attach to my camera and then allow me to screw it into the 42 or 43mm threaded opening of the extender?
  3. I've been watching the moon around the same time (19:10-19:30) for the last few evenings at around 19:20 a black object flies diagonally across it. I checked Stellarium and played the sky backwards but couldn't see any registered objects. Is it common to witness orbiting debris? I had wanted to take some pictures of it but it's just too fast and the focus on my phone is playing up at the moment so videos are useless. As a side note, I managed to get some lovely pictures of the moon (my first ever). Viewed with an Orion Optics 150/750 Europa series and unbranded 25mm and 10mm lenses. Did a bit of fiddling with the light levels on my phone too.
  4. I suppose I'm looking for some guidance with what constitutes a high quality or lower quality barlow, and what brands tend to fall in each category. It seems I'm looking at a particular price range! Amazon and Tringastro are showing a sneaky £59 £24.95 "sale" price. I don't know really, in the range of £30-50, which on further inspection limits me to more entry level equipment I think. I'd like to know more about choosing the right eyepiece for an object. Is it a good rule of thumb to say higher magnification is better for viewing planets? I'd like to make the image of the planets larger, I know they won't necessarily become more detailed with magnification. Is it possible with this telescope to view deep sky objects well? Or is it really down to increasing focal length/mirror diameter?
  5. Ah that's good to know! Is there a way to find the point of focus to get a proper measurement? I've tried shining a light into the telescope and holding a piece of paper outiside the eyepiece but can't seem to get a focussed beam. I think it could well be part of the Europa series, it does have a single vane secondary support instead of a "spider". I'm looking at possibly picking up a cheshire, is a laser collimating eyepiece worth the extra expense? I'm also looking at barlows now. I can get a Celestron Omni for £25 instead of £60, but wondering if it would be better to invest in a higher quality barlow for any future high quality eyepieces/telescopes I might get. Looking at a Meade #126 x2 Barlow Lens 1.25" or a Revelation Astro 2.5x Barlow Lens 1.25". Does anyone have advice in regards to these choices? Would I really be better off buying say, a 6mm eyepiece for higher magnification instead of a barlow?
  6. Hello, I'm new here and to telescopes in general, though I've been doing some heavy research. I'm looking for guidance with a reflector telescope we picked up in a second-hand shop some years ago now (photo attached). The only identifiable marking on it is a sticker that says "Orion Optics". No model number or anything. The measurements are as follows: -The tube is 6.75" (170mm) in diameter, 27.5" (697mm) length. -The primary mirror diameter matches the opening aperture, just shy of 6" (148mm) -The distance between the primary mirror and the centre of the eyepiece slot/secondary mirror is 21.75" (550mm) -We have two unbranded Plossl lenses (25mm and 10mm) Now, because there is no model number, I can't look up what the focal length might be. I'm assuming it is the raw distance between primary/secondary mirror, so 550mm? I think this puts it in the f/5 ratio, which is good for wide-field viewing as I understand it. We get lovely views of the moon with both lenses, but have had less satisfying views of venus, jupiter and saturn. If the focal length is as I assume 550mm, then the magnifications we are getting with 25mm and 10mm lenses would be 22x and 55x respectively, right? I've read that to achieve good views of the planets you need upwards of 150-250x magnification (if your telescope has that capacity). If the capacity is roughly 50x the diameter, then we should be able to achieve 300x magnification (atmospherics allowing) with this scope. I've been looking at getting a Barlow to use with my current lenses (the 10mm should net us 130x with this) and buying another lens closer to 5 or 6mm to use with it also. Is this wise? Does anyone have any recommendations? Summary of my questions: -Are my assumptions about the focal length of this scope correct? -Will a Barlow lens and a smaller focal length lens help achieve better views of the planets with this scope? -Would replacing the unbranded Plossl lenses yield clearer results? (Are all lenses created equal?) -The scope has never been collimated by myself, so I imagine it needs a tune up, what's the best way to go about this without dropping £££? I have good practical ability so no worries there. -I can see lots of dust on both mirrors, is it advisabe to clean them? One last thing. Last night I managed to locate Andromeda galaxy, but it was only faintly visible with binoculars (if I looked around it rather than at it), less visible in the viewfinder and totally invisible through the telescope itself. Is the only way to see deep sky objects like this to have longer focal length and wider diameter scopes to collect more light? I know increasing magnification decreases brightness of the image so more powerful lenses won't help for deep sky objects. It was fairly low on the horizon, in a well-lit town, with a nearly full moon in the sky, so yes, visibility conditions were less than ideal! I'd like to start planning to build a telescope specifically for deep sky objects, so if anyone has any suggestions please let me know. I know I had more questions but I've run out of steam and don't want to scare anyone off from answering this beast. Thanks in advance for any replies!
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