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Luna-tic

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Everything posted by Luna-tic

  1. If you don't have those basics, none of the rest will make much sense. Knowing the Moon, planets and stars, constellations, clusters and galaxies can be learned by rote memorization, but that gets boring when they're not put into perspective with each other. Go outside at night and look UP, take a pair of binoculars with you. Find objects that pique your interest, make lists. Learn what they are, where they are and how they came to be. (Crab Nebula, M1, NGC1952, Taurus A [same thing]; ~6500 light years away, remnant of a supernova that was visible in daylight in 1054. First astronomical object associated with a supernova explosion). Things like that. One question gets answered, three more questions result from the answer. Astronomy is something that can't be learned in a few years, there's just too much to it. Even professional astronomers focus on one area of the science. As you pick up on some aspect of the science, other things begin to fit in and it all makes better sense, and the learning begins to cascade. If you don't have it, download Stellarium. It's free and will open the sky like you've never seen it.
  2. I own both a C6 and a C8 (Edge HD 8"). "Portability" depends a lot on how you plan to tote it around. The C6 is 10 lb., the C8 is 12.5 lb. , but the C8 is a bit bulkier; look at the included pictures to see relative sizes. The mount looks okay for either one, but you'll be pretty close to its weight limit with the C8, a diagonal and a large eyepiece and a finderscope. You'll probably experience more movement of the assembly when observing, and photography is pretty much out. I prefer EQ mounts myself, and the Celestron Astroview is about the same price, but could tolerate the C8 better. If you can swing the extra dollars, I don't think you'd regret the larger aperture of the C8 at the expense of a slightly larger tube. There is no difference between the two tubes except the color. I also prefer black, but for $200 less I could easily get used to orange.
  3. If the corrector is clean, you should be able to inspect the mirror through the front of the scope.. If the scope has never been opened, the mirror should be in good shape.
  4. If the price is right, I'd say go for it. The picture shows an alt-az mount with a wedge; the wedge makes it into an equatorial mount. Google for good descriptions of mount types, and the benefits/downsides to each one. The C5 is a Schmidt-Cassegrain design, a type of catadioptric telescope. This means it uses both mirrors and lenses in the design, where a Newtonian uses mirrors, and a refractor uses lenses. The focal ratio of a Schmidt-Cassegrain is typically f/10, and the focal length of the C5 is 1250mm, fairly long for the actual length of the scope. SCT's are compact-for-aperture, and great for looking at the Moon or planets, less so for some deep space objects because the field of view can be too narrow to see certain objects in their entirety. The focal length of 1250mm gives you a range of about 30x to 250x depending on your eyepiece selection. The compact size makes them pretty easy to carry around and set up. C5's are sold as spotting scopes (for birding and target checking), and are fairly robust. The corrector plate (clear lens in the front) can be broken if it gets hit, and the secondary mirror in the corrector's center can get out of alignment. This isn't a failing of the C5 inparticular, just a trait of Schmidt-Cassegrains in general. The mirror is easily realigned and is expected to need alignment (called collimation) from time to time, for optimum optical performance. I own two Schmidt-Cassegrain telescopes, a 6" and an 8", and love them. They gather quite a bit of light and give a nice, bright image, and are great general purpose telescopes.
  5. Just the OTA, or the entire setup (tube, mount, tripod)? I built a carry-all for mine, two wooden boxes (padded) that will clamp together and fit on a fold-up hand truck. Great for storage, and you can haul the entire kit out to an observing site in one trip. The EP case and a second telescope tube strap to the top. A commercial alternative would be to find something like a Plano or Pelican hard case in a suitable size and shape.
  6. Wow, the flash on that video was impressive!! On the other hand, it couldn't have been much. Our local news would have immediately suspended all programming, flashed "BREAKING NEWS" on the screen, and then gone live to someone's back lawn with cameras pointed at the sky, waiting on another one to fall and filling in the dead space with uninformed chatter about the world ending. And I'm only about 700 miles from where it happened. Actually, I wonder if my local news will even report it. Doesn't rate with wrong-way drivers on the freeway.
  7. I was also surprised how faint it is. Sometimes Stellarium can really be misleading, even after you get used to it. I tried looking visually, all I could see was NGC 2244 (the cluster). I was freezing to death, it had dropped to 16*F by the time I got around to the Rosette, so I tried a quick EPP shot through my frac with my DSLR, and got this single image below. Sorry the focus is off, but this was ISO 6400 at 30 seconds, unfiltered with a 13mm EP, and you can just barely make out the nebulosity of NGC 2238.
  8. So far, it has to be the moment of 2nd Contact during the Great American Eclipse last August.
  9. Essentially the same, optically. I have the one with the T-mount, it's a decent Barlow for the price. I occasionally use the lens assembly on the bottom of an EP, it gives 1.5X magnification that way (a 25mm EP becomes a 16, a 13mm becomes a 8.6, etc.) and I've used the barrel as a nose-piece for my DSLR. Oddly enough, I've not used it as a 2x for photography, I suppose I forget I have it because I have a couple of EP's I can use for EPP.
  10. Much more than that, actually, although for our purposes only Alcyon and the three companions would be visible. According to the Washington Double Star Catalog, there is the main star Alcyon (Eta Tauri); the three visible companions "B"(24 Tauri), "C"(V647 Tauri) a variable, and "D", itself a double. Its components are roughly equal mass and orbit a common center of gravity and are about 0.3 arc/sec apart. There are an additional 4 close companions, all with magnitudes fainter than +11 Alcyone is itself a triple; Alcyone A is the visible, apparent mag is +2.87. One companion (B) is tiny and orbits A less than one milli arc/second with a period of about 4 days. "C" is about 1/2 the mass of A and orbits about 0.031 a/s distant, or roughly equal to the orbit of Jupiter around the Sun. I'd bet that from a distance close enough to see them all, it would be spectacular.
  11. Odd that Stellarium calls it "Merope" Nebula, since the nebulosity isn't directly related to the cluster, but just something they are passing through. It was at one time called the Maia Nebula, for another star in the cluster. Seems like the group as a whole are very popular to view wide-field, but Alcyone is fun to look at in high power, to try and pick out some of the multiples. It's a sort of "cluster" in a cluster, all by itself.
  12. You're right, I stand corrected. But since it looks yellow to us when looking up at it unfiltered (except for the atmosphere), I feel it's more 'natural' when looking through a filter that colors it that way. Besides, it is a yellow dwarf.
  13. My W.O. GT81 APO f/5.9, on the mount with my Edge HD 8"
  14. The Esprit 80 on your list is a good bit more than the GT81, although it is a bit faster (f/5 compared to f/5.9). I paid $1150 USD for mine, including the f/4.7 reducer/flattener made for it. The 20th Anniversary Edition comes with a set of guide scope/finderscope rings, mounted to a nice carry handle. It also has a dovetail foot like the Esprit 80, but unlike the Esprit, the foot unscrews from the bottom, and a set of 90mm rings is available from WO as an alternative to the foot. The carry handle also removes easily, and the finderscope rings can be removed from the handle. It's well thought out. The finderscope I have attached is the 9x50mm one that came with my Edge HD 8" The dovetail foot is drilled/tapped so a larger dovetail can be affixed to it, same as my GT81. This is the option I chose; downside is it doesn't provide for rotating the orientation of the scope, but that doesn't bother me. I used a universal 13-1/4" Vixen-style dovetail. The two knobs on the dovetail are stops to prevent the scope from sliding off the mount saddle should the screws loosen. They fit in slots and allow forward-backward positioning on the mount to account for balance. Not sure if the Esprit's body is long enough for a set of rings, They might impede the movement of the dew shield.
  15. I noticed you have mostly 80-size scopes listed, except for the GT71 and ES 102. I have a friend who just picked up an ES 102 with the carbon fiber tubes, it is gorgeous, but he doesn't care for the focuser. I have no other experience with it, or any of the others except the WO scope. I have the GT81 20th Anniv. model. Any reason you chose the 71 when most of the others you're looking at are 80-ish? (Cost, maybe?) I'm floored by the GT81's quality and finish. The optics are superb and the focuser is smooth as glass.
  16. Sounds to me like a telescope for those who 1- expect to look at something that visually is not much more than a fuzzball, but expect it to look like a Hubble image, and 2- don't want to spend the time and money nor have the desire or patience to learn AP. Basically, it's a Schmidt Camera that you can look through.
  17. This is from the August '17 total eclipse, shot through the Thousand Oaks film from a C6. The color, I think, is as much like the natural Sun, minus the extreme brightness. It allowed a really crisp focus, too.
  18. Protect the film from abrasion, fingerprints and pinholes and it will last almost indefinitely, it's a polymer plastic. I have the Thousand Oaks film, very similar but gives the visible disc a nice orange color. I made one for each of my SCT's and nest them with a piece of cardboard between them, inside a metal round cookie tin, like the ones you give at Christmas.
  19. What all the guys above me are recommending are excellent ideas. Budget is a huge consideration, things get expensive really quickly, and to start out, you'd like to maximize the "bang for buck". I sort of knew what I wanted when I started, and worked my way into it with that in mind, prioritizing what I wanted first. You can look at my signature to see what I now have. The refractor gets me the wide-field views you are apparently interested in. However, mine is an "apochromatic" (three color corrected) scope that works great for photography. An "achromatic" is less expensive for the same focal ratio, and color corrects for two colors. Doesn't work as well for photography, but still excellent for visual. My small SCT is a longer focal length and gives a narrower field of view than the refractor, but has greater aperture and a higher overall magnification capability, but the focal ratio can be changed to widen the field a bit, making it pretty versatile. The larger SCT ramps up the attributes of the smaller one, plus is more optimized for photography, but still can't match the wide-field capability of the short focal length refractor. There are some telescopes that can serve as general purpose and do a decent job at it, but no one telescope will be outstanding at everything; it's a compromise between cost, size (aperture), focal ratio and purpose. You also have to figure the mount into the cost and purpose. If all I wanted was a telescope to observe with, and wanted to keep the cost down, but wanted something large enough to grow with (keep for a while and have it remain adequate), I'd look for a f/5-f/8 Dobsonian with a 6" to 8" mirror. To find objects without a Go-To, you'd need to learn the sky with something like Stellarium, or buy the book Turn Left at Orion, or install a star-finding app on your smartphone, that you just hold the phone up to the sky and it shows what's up there. Then aim the scope and look.
  20. Loving my AVX, but haven't experience with others so I can't objectively compare. I can get round stars at 30 seconds doing single image photos at f/10, haven't started stacking or guiding yet.
  21. Consider during your search that the larger the f/ ratio, the narrower the native field of view will be. If you want wide-angle views, something on the order of f/7 or less. Large aperture Newtonians can get wide field and good magnification at lower f/ratios, but as yo go toward f/10 and above, the field starts closing in. If all you want to do is visual (no/limited AP), look for something in a small Newtonian/Dobsonian in the f/5-f/7 range on an alt-az mount, or a 3" (80mm) refractor in the f/7 range. A doublet achromat should be affordable. An alt-az Go-To isn't hard to set up and takes a lot of work out of looking for things to look at.
  22. At native 1500mm, f/10, I'd say about all you need to add is a 2x Barlow or Powermate. At f/6.3, I agree with what Stu says above. The only reason I'd use an EP with my reducer is if I'm doing EPP through it. For visual, I'd use my lowest power EP, so I could enjoy the wider FOV the reducer gives, but that's about it.
  23. I also have a C6 with the reducer, and an Edge 8 with the .7 reducer. I never use either reducer unless I'm taking pictures. What's the point of widening your FOV by effectively decreasing the focal length, then viewing with a small (high magnification) EP and tightening up the FOV again? My APO's reducer doesn't even give a visual option.
  24. I tell them that I ask myself the same question frequently, but haven't come up with a reasonable answer yet.
  25. Luna-tic

    John Young

    His list of firsts is incredibly impressive, even within his peers. First astronaut to pilot AND command 4 different classes of spacecraft: Gemini, Apollo CSM, Apollo LEM, and the Shuttle. First manned Gemini mission First (along with Michael Collins) to rendezvous with another space vehicle (Agena) First man to fly solo around the Moon (CSM pilot on Apollo 10) Commanded the first Space Shuttle mission Longest career as an astronaut (42 years with NASA) One of only three men to have been to the Moon twice (James Lovell and Eugene Cernan are the other two) One of twelve men to walk on the Moon His Naval Aviation career is no less impressive, with a total of 15,275 flight hours in prop, jet, rotor, and rocket powered vehicles, and 835 hours of space flight in two Gemini, two Apollo, and two Shuttle missions. He owns two "time to climb" records in the F4 Phantom. This guy had the Right Stuff in spades.
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