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Dunkster

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Everything posted by Dunkster

  1. Welcome Scott! Optically it's not a bad little scope, but the eyepieces aren't up to much (bundled ones usually aren't!) and the worst part is the tripod. It's a little on the flimsy side and moving the telescope on the tripod would try the patience of a saint I'm sure if you already have a good quality photographic tripod, it should mount on their no problem though, as I believe the thread is the same. The best advice would be to look into whether there's an astronomy society/club/group near you and visit on one of their open sessions. There you'll get to see a variety of different telescopes and their equally varied owners and get to see what's what. Just to set your expectations, there are good (and slightly larger) telescopes that start at a little over £100, but obviously that is a little more than the travel scope 70
  2. The 25mm is heavier than the 30mm by about 200g it's a big lump for sure
  3. Heavy? Meade's otas might be heavy, but Celestron's (at least up to 11") are lighter than the nearest size SW newt Are you sure you're not cursing Meade for the sins of the universe Olly?
  4. Big garden?!? It might be if half of it wasn't taken up by the flippin pool And sunshine... wettest June in 6 years followed by 10 days of fine weather (around new Moon luckily) and now thunder storms...I despair
  5. Nice catch! Looking forward to Jupiter being back in the sky, Saturn has been great this year but Jupiter is so much more dynamic
  6. See, you guys are so hung on on cool down, and then stick honking fans on Dobs.... it's simple... keep it outside!
  7. It's a bayonet fit, like a light bulb! You just need to feel for the knobbles on the outside of the ota and line up with the entry point on the cap... simples!
  8. How about a 5" Mak or 6" SCT? Compact, light, within budget (used), decent with planets, easily mounted...stick a nice optical finder on top for the wide stuff Depends on your vision of transportable though.... I moved recently and took the C8 in a flight case, tripod in a tripod bag, eyepieces and accessories in my laptop backpack. One on wheels, one on my back and one in the hand! Transportable, but I couldn't go hiking with it.
  9. It depends what you are trying to achieve... the 100s are bigger, heavier and pricier than any of the 82s (except 30!) but do give that extra wide FOV. The difference in FOV (longer over shorter FL) between the 25(100) and the 30(82) is about 5%... the 20(100) and 30(82) is about 23%, the percentage changes from 20->14 and 14->9 are larger than that (42% and 56%). So it depends on whether you want to space out your FOV, EP focal lengths, get a wider FOV across the board or <insert here>
  10. Good point, I think they just went for 2" barrels for security, as looking at the specs the shorter FL ES100s are heavier than the adjacent Ethos (9mm ES100 is 100g heavier than 10mm Ethos, 14mm ES100 is 246g heavier than 13mm Ethos) and both ranges are on the large side Maybe there's something more complicated about it, beyond my simplistic understanding of it
  11. I've only got a metal tape, which doesn't bend very well but kinks... it reads 29" around the end, 28" around the tube just behind. Paul's right, you should heat just behind the thick part at the end for better heat transfer. The Celestron reducer has a male SCT thread on it - so you screw on whatever you normally would on the end.
  12. Congrats on your new scope Nick, sounds like a cracker
  13. The SVR-90T is supposed to be a fine scope from what I've heard The most popular Cassegrain designs round here are the Schmidt (and modified Schmidt) Cassegrains and the Maksutov Cassegrains... Both use a primary mirror in much the same way as a newtonian reflector, so the weight issue is related to the size of the mirror (for any type of reflecting telescope) Both also use a corrector plate, relatively thin on the SCT but thicker and heavier on the Mak, correcting for spherical aberration, but can make them susceptible to dew if the thermals aren't controlled (or if the atmosphere is overly humid, like the UK ) The down side with having both ends closed is that it traps air that for best results should be in equilibrium with the ambient temperature. That doesn't mean it can't be used while cooling! The internal thermal currents affect high magnification viewing, so common sense says use lower magnification in the meantime They tend to suffer with field curvature and a little coma too, the latter usually being fairly small because of the long focal ratios, however some recent modified designs have sought to reduce/eliminate one or both of those, but these are not cheap compared with bog-standard SCTs. Newtonians typically suffer badly with coma the faster they get (below f/5?), and people use coma correctors (at additional cost) The long focal length restricts the maximum field of view, as they are inversely related. If you want a wide field scope, use a small refractor In reality, most except the largest subjects will fit in the FOV as even the C11 can show almost 1 degree across, but focal reducers exist that shorten the effective focal length thus widening the field of view (depending on model, etc) The long focal length also means that high magnifications are achieved with longer focal length eyepieces, compared with faster focal ratio scopes. In these days of long eye relief Delos and friends available in short focal lengths, this is less significant The biggest gripe folk seem to have about these things is price, which is dictated by the manufacturers/distributors, and likely related (at least in part) to their relative complexity to manufacture compared with some other designs.
  14. That is your preference based on characteristics you value, which by definition are not objective statements! The C14 is 20kg, within the 25kg load capacity for visual of the NEQ6 as quoted by FLO here http://www.firstligh...ro-synscan.html The C11 is 12kg, as listed by Celestron here http://www.celestron...-a-xlt-cge.html Height depends on the individual. With the tripod-based mounts used commonly for SCTs (Meade LX, Celestron CPC, any GEM...) the height can be adjusted to the preference of the observer. This is not a design feature of the Dobsonian mount, however the height of the eyepiece using a Dobsonian mount is dependent on the altitude of the object being viewed, whereas the height of an eyepiece using either an equatorially or alt-az mounted SCT is much less variable. Likewise, the space taken up by the mount is fixed with a Dobsonian mount, but variable with any other type of mount. Typically the mount unscrews into multiple pieces, at least tripod and mount head be it equatorial or alt/az.
  15. Gutted! Yeah it's a bit weird with our favourite constellations going past upside down but I'm sure it's something to get used to
  16. Nice road test, glad you got some light through them you've got some useful FLs there too! Saturn is about at the moment, but maybe this is jaded by the twilight up there at the moment? No matter, the king of planets will be back in our eyepieces in a while
  17. You should get along to a meet of a local astro group where someone has one of the models to demonstrate, as each persons expectations are different and you don't seem to have a lot of luck ... so good luck with your choice
  18. Nice report, Andy thanks for sharing, good to see all that can be had with a 130 You guys need to get yourselves down to Olly's place in France or down here to the Southern Hemisphere... the extra altitude makes them much easier and clearer to see, and darkness helps a lot, so another month or so should push most of southern England into darkness.
  19. Nice bunch of targets there Nick, thanks for sharing
  20. Sounds like a challenge for the C8 then but there's those funny white fluffy things dotted about the sky
  21. Never say never :D Any luck last night?
  22. I think the C11 would definitely be a stretch IMO. Not just the weight, but the focal length...you'd need a good finder scope and have it aligned accurately with the main scope. Also the slow motion controls would need to be really good
  23. Didn't you used to have a C8 Edge HD or am I confusing you with another member? (Sorry, old age, memory loss...)
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