Jump to content



  • Posts

  • Joined

  • Last visited

  • Days Won


Everything posted by brantuk

  1. Put your scope, eyepiece, and target info in here and it'll show what you should see in the fov: http://www.12dstring.me.uk/fovcalc.php You can play around with different scopes, eyepieces, cameras even and work out what you can expect to see or image. A 10mm eyepiece in a 250px just shows mars as a dot.
  2. I didn't think it was anything to do with "inclusivity" in the modern, trendy, (oft misused) sense of the word. There were groups for all types of scopes, and nothing and no-one was "excluded" - literaly "anyone" could set up a group for "any" type or size of scope. None of the groups were private or "closed" iirc - but one did have to join the group. But that's where the problem lay - it took the subject matter off into a separate area and away from the main boards reducing it's visibility and availability without some kind of prior knowledge and searching. Fine for established members, but made it unduly inconvenient for newbies, and reducing activity in the general threads. Like Neil says - the current arrangement " emphasises the benefit of keeping all topics open to all " - and anyone can still start an equipment specific thread, but in a general category board with higher visibility.
  3. I remember the vintage group. It was at a time when there were several groups for different types of scope. I set up and ran the Dob Mob group which was very lively, and there were groups for macs, fracs, sct's, etc, and even some specific sized scopes - all were very active. I was a mod at the time and iirc a discussion about all the groups resulted in the feeling that scope groups took too much subject matter from the general forum. It was also at a time when specific social groups were active and everyone seemed to be going off into their own corner of the forum to discuss their own particular social / geographical area, or equipment. So scope groups were disbanded and the subject matter came back into the more general, rehashed main forum boards. (So no - you're not going gaga Phil lol )
  4. Some folks do specialise in solar system objects or even single planets. And the two scopes you mention are fine for that. However it's more common for astrophotographers to widen their remit to include the deep sky (there's a lot more stuff out there). An equatorial mount is the far better tool to cover all types of object. It enables you to track in a single plane (rather than two axes), facilitiating long exposure photography. Then you need to choose a scope - a newtonian or a refractor of the right spec are usually chosen for deep sky objects - cassegraines have a narrow fov and long focal length - which are great for planets but not so much the deep sky. I would recommend you get her a copy of "Making Every Photon Count" by Steve Richards first - it's an easy read and covers most everything you need to know about AP. Welcome to SGL. https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html
  5. It doesn't matter what it means cos they'll never be able to decode it - and even if they do, we didn't put the postcode on so they won't know where to look for us.
  6. Warm the lens for ten mins in your pocket before using it. Also check the "seeing" conditions - you might e.g. be looking through thin cloud high up in the atmosphere. Ensure your object is high - looking at stuff just above the horizon will appear fuzzy cos that's where you look through the most atmosphere. If observing with a group - try someone elses eyepiece to compare with yours and ensure yours aren't dodgy. Make sure you know what magnification you are using - over magnifying the object also magnifies impurities in the atmosphere making it appear fuzzy. Try viewing without the fan on - it may be vibrating the scope and fuzzing the views - I had this once on my dob. Just a few tips that might help you get going.
  7. Congrats Francis - nice buy I'd be interested to know your impressions of the mirror in this scope, when you get it going.
  8. Interesting question "Would I be able to buy it all again?"...... I guess we're inferring everything will be more expensive in the event of a hard brexit. The thing is - I remember when we first joined the EU, and doing so didn't automatically make everything cheaper...... so why would the opposite be true? In fact - joining in the first place ultimately inflated prices by a factor of nearly two and a half times. It's all a walk on slippery rocks. lol
  9. The telegizmo's are one of the better makes of cover. They're breathable and protect from ultra violet rays as well as poor weather conditions. I see them in use all the time at star parties where scopes are left outside 24hrs per day for up to two weeks or more. However, in home use, my personal preference is to bring a scope indoors just for security purposes, and to save wear and tear on covers.
  10. I would also advise a good read of "Making Every Photon Count" by Steve Richards. It's the astro imager's bible and will tell you all you need to know about photographing the night sky, including cameras, telescopes, object types, and photography techniques. It's a very broad, deep (and expensive) subject with a steep learning curve, and understanding the main principles is essential to be successful.
  11. Congratulations John for such a great contribution to the forum!
  12. Yes it's around f-9 that one and you'd need a 3mm eyepiece to achieve 233x magnification (not realistic). But the overriding thing against that one is that you want to do AP and that scope doesn't have a motor - so your pics are going to be very limited. You really need to track objects electronically, and you seem interested mostly in planets which are bright and near. For that, a long focal length will give you sharp, contrasty pics. The atmosphere will affect most images so you need to take lots of them (thousands) and merge only the good ones together and process the results (eg with Photoshop). The good shots will come in very short moments of astmospheric stability which do occur from time to time. I'd recommend either a long focal length refractor or maksutov cassegraine - you'll get 1200-1500mm focal length at around f-10 to f-12 which is fine. You'll need to mount it on a good tracking/goto mount like the Skywatcher HEQ5 - but you can get some reasonable starter mounts like an EQ5 with tracking motors only, if you just want to dabble. Or the Skywatcher Star Adventurer. A webcam can be used for imaging, or get one of the popular solar system astro cameras. A good book to buy is "Making Every Photon Count" by Steve Richards. I don't know your budget - but I'd up it to around a grand for a realistic start using well chosen second hand gear. Your dslr would be better deployed with a fast lens to image deep sky, wide field objects. Hope that helps.
  13. I've met Peter Drew many times at star parties - a lot of folks don't realise how significant he is in the world of astronomy, mostly because he's such a nice and modest chap. But you get talking to him and find out about the stuff he's done and you'll be fascinated. I was very flattered the first time he came to look at my solar scope when it was a new model.
  14. If you have the counterweight system on the scope and you remove one of the cameras from a well balanced system - then you need to rebalance it all. I think it may only be a matter of moving the counterweight along the bar an inch or two. If that doesn't work then you could try sliding the frac up or down the dovetail bar. Hth
  15. With cheaper scopes, there tends to be less emphasis on "figuring" of the optics and quality of glass/mirror used - just the bare minimum to justify the notion it's a telescope, and they slap it in the tube, often with poor fixings, and pop it on a low quality wobbly mount/tripod. Seben have done a lot of this in the past and their scopes have needed so much modification you may as well have spent the money on something that works outa the box. Imho they're ok as project scopes, or for kids to dabble in the hobby without spending a ton. But if you want a trouble free scope from the get go, up the budget a tad and get a SW 130P. Hth
  16. The bright one is a star - all stars are dso's. The smudge below could be a more distant star or even a nebula - again both dso's. But it is deffo out of focus. The general shape and orientation in the sky could suggest M42 (Orion Nebula) under Alnitak - but really there's not enough info in the pic to be sure - unless you know you were looking at the constellation of Orion. (Download Stellarium - it's free and a great way to know where you are looking in the sky - welcome to SGL)
  17. Here you go: https://www.365astronomy.com/The-Night-Sky-Star-Map-Celestial-Constellations-Umbrella-BLUE.html?gclid=EAIaIQobChMI_bvJ77vR2QIVqLXtCh0ltQcVEAYYASABEgJnmPD_BwE
  18. As above - but also make sure it's well ventilated to avoid condensation build up inside the scope - especially in your C925. I've seen water swilling around inside the tube of Mak's and Sct's and it's a devil to get out.
  19. Hi Paboy and welcome to the forum. The answer to your question is double edged I'm afraid. Telescopes only gather light and focus it - they don't necessarily enlarge it. The larger apertures will gather more light than smaller apertures and their ability to focus depends on the focal length and focal ratio of the scope (amongst other attributes). For seeing close objects like planets you get a sharper, higher contrast view from longer focal lengths and higher focal ratios (e.g. an f-12 Maksutov with 1500mm focal length). For seeing objects deeper into space, a low focal ratio and wider aperture is more important (e.g. f-5 dobsonian with 16" aperture). To "enlarge" what you see in the scope we use eyepieces of different focal lengths and magnifications. Magnification is given by scope focal length divided by eyepiece length. So a fl=1000mm scope with a 10mm eyepiece will magnify 100x. We also use barlow lenses typically 2x and 3x to further multiply the magnification factor. How far you can go with magnification depends on the atmospheric transparency and how "clear" the weather is - what we call "the seeing". When it comes to photography however, this is mostly done at the prime focus of the telescope, and you are looking for a scope that focuses two or more wavelengths of light at the same focal point to achieve good colour. Also desireable is as flat a field as possible, little or no chromatic aberation, and coma free. Then it comes down to image scale and how many pixels are used to record the photons of light being captured by the camera. Telescopes with lower focal ratios will gather light faster than those with longer focal ratios - amateur astro imaging tends to be done around f-5, preferably with the clarity/contrast provided by refractors, though some use reflectors as well. The focal ratio determines how long it takes to capture an image, lower fr = faster capture and requires lower exposure times. Magnifying adaptors are sometimes, but rarely, used. I would recommend a good read of AP imaging principles before getting a scope/camera combination. And do go along to your local astro soc where you'll get loads of advice and see examples of equipment used for both observing and imaging. A good book for amateur AP is "Making Every Photon Count" by Steve Richards.
  20. Pop a "Want Ad" in the classifieds "For Sale or Swap" is your best bet. Totally agree the best scope is the one you use. Welcome to the forum!
  21. £150 'ish would be a good average depending on age and condition and negotiating skills.
  22. Yes it's a shame the car parks are locked overnight at Bradgate - same at Beacon Hill too. I usually run out to Wymeswold to meet up with the guys at EMS. I occasionally go with Leics Astro Soc to their dark site near LFE - though I'm not sure where their current site is exactly. If you need any details let me know and I'll happily dig them out and PM them to you.
  23. Whatever eyepiece you buy check it will give you the width of field you require and the correct magnification you're after. You should also beware of eye relief and also think about the size of aperture you'll be looking through. We all see differently (including people who wear glasses) and you really want to ensure the eyepiece fits you personally as well as your scope (or scopes if you have more than one). I always check the technical specs on a retail site first and estimate the used price to about 50% to 70% of the "new" price depending on age and condition. Bear in mind some folks will build in a little leeway for negotiation, especially if you're buying more than one item from the seller. You can also ask about the condition of the rubber eye guards, and how it's been cleaned and how often. Pay special attention to the coatings too. Good luck.
  24. You may want to consider buying or making some library steps for your son. If you make one then you can pick the weight, materials, and number of steps, as well as the width/depth of each step to provide a solid platform for him to stand on. Something like this can be very useful - even for some adults (who I have seen using them): https://www.google.co.uk/search?q=library+steps+with+pole&dcr=0&tbm=isch&source=iu&ictx=1&fir=cnqRbqX3SsQNJM%3A%2CvEnHleTN8tNswM%2C_&usg=__mFe3-4DBpzPg4cOoi_RnpQOnoBE%3D&sa=X&ved=0ahUKEwjK9JS_prLZAhVFNMAKHTArDIIQ9QEILTAC#imgrc=qmOXhN4Ee3OZkM: Also - a shroud is easy enough to run up from thin camping foam or black material - so don't let it put you off the truss design. A 130 offers more light grab than the 100 and will give access to more and deeper space objects, and better contrast and clarity on near space (planets etc). Hth
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.