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brantuk

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About brantuk

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    Hyper Giant
  • Birthday 09/12/1954

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    Male
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    Leicester
  1. Newbie question

    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)
  2. Here you go: https://www.365astronomy.com/The-Night-Sky-Star-Map-Celestial-Constellations-Umbrella-BLUE.html?gclid=EAIaIQobChMI_bvJ77vR2QIVqLXtCh0ltQcVEAYYASABEgJnmPD_BwE
  3. 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.
  4. 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.
  5. 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!
  6. TAL 100R price?

    £150 'ish would be a good average depending on age and condition and negotiating skills.
  7. 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.
  8. Buying 2nd hand eyepieces

    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.
  9. 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
  10. newbie

    For the first manned space flight to the moon, NASA didn't know much about the moon and where was a suitable place to land. So they asked Sir Patrick Moore about the moon and what he thought about where to land, because he was the leading authority in the world who had studied the moon more than any one else at that time. Indeed he was NASA's main consultant for the moon landings at the time. And as Geoff says above, that knowledge has developed a lot since the actual landings. So I would think both sources of information are going to be useful.
  11. Telegizmos are amongst the better scope covers certainly. They're great if you're at a star party or some other temporary dark site for a few days. I personally wouldn't leave a dob out permanently though. The metal and mirrors would be fine so long as you don't get any insects all over them. But my concern would be the wood, wide temperature changes, condensation, and damp. The smaller dob bases tend to be chipboard which can warp if any moisture gets in. Keeping them indoors or garage/shed would be far preferable imho.
  12. Dec balance

    Ok so which way does it fall when both clutches are unlocked? Does the RA fall on the weight side or scope side? And in Dec, does the scope fall on the meniscus end or camera end? Is it a slow fall or sharp fall? If you can describe in more detail I may be able to suggest something to help....
  13. I had an adaptor made to fit an EQ5 tripod: https://www.eastmidlandsstargazers.org.uk/gallery/image/177-kims-adapterjpg/ Any engineering workshop should be able to run one up for you - unfortunately the chap who did mine no longer makes them or I'd send you to him. You might find someone on the forum with a workshop who can sort it for you.
  14. Dec balance

    With the RA locked you only need to balance Dec in the horizontal plane. If it deffo won't balance then you may need to add weight to the rear end of the cell (eg using a weight bar kit) - or possibly use a longer dovetail. Maks can certainly be a little tricky.
  15. Questions to ask an astronaut..?

    No one can hear you break wind in space lol
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