Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Stargazing Telescope lens upgrade

  1. Jul 25, 2005 #1
    IS it possible for this one?

    I was given an older Meade telescope today the specs:

    StarQuest
    Model: 60AZ-M
    60mm (2.4") Altazimuth refratcing telescope

    Lens specs:

    - 5x24mm viewfinder
    - SR4mm H12.5mm and H25mm eyepieces (0.965" barrel diameter)

    - 2x Barlow lenses


    What can i upgrade on this thing? It's quite old
     
  2. jcsd
  3. Jul 25, 2005 #2

    russ_watters

    User Avatar

    Staff: Mentor

    That's an el-cheapo/K-Mart special and not really worth anything. As a beginner scope it'll provide more frustration than anything else.

    Those things come with a barlow lens and 4mm eyepiece so they can advertise 450x magnification (probably a 900mm focal length), but in reality, anything over about 100x will be too fuzzy and moving to fast to see.

    If you're feeling lucky, try viewing the moon and Jupiter (look south just after sunset for Jupiter) using the 12.5mm eyepiece.
     
    Last edited: Jul 25, 2005
  4. Jul 25, 2005 #3
    Okay, that's what i was thinking, thanks for the info. I'll be looking forward to dropping $300-$400 on a new telescope then, next month. Any suggestions?
     
  5. Jul 25, 2005 #4

    turbo

    User Avatar
    Gold Member

    What would you like to do with the 'scope? Given the humidity and atmospheric turbulence you can experience there (sandwiched between the ocean and the mountains), you might want to attend a few star parties given by local amateur observing groups and see what those folks are concentrating on observing, and what equipment they favor. Someone on the east coast of the US or in Japan might like to see if they can catch a comet (with suitable telescope) and put their name on it. Someone in a very dry area might favor a very different design than someone from an area prone to dewing, fog, etc. You can see what I'm getting at, I hope. Here in Maine, summer is not always that great (haze and pollution from upwind), but there are nights that are very good. If you can "suit up" for those cold (-10 to -20F often) February nights and store the scope in a very cold space so it doesn't need lots of cool-down time, winter skies can be fantastic! Sometimes the Aurorae swamp out the sky, and you have to just take pictures of the colored curtains, sheets, and rays, but that can be fun too - it just sucks when you were planning to take a very long guided photo of a cherished deep-sky object and you glance up from the guiding eyepiece and notice that the sky is so bright you could probably read a newspaper out there. :yuck:

    BTW, for anybody who lives near 45 deg latitude or higher in either hemisphere, if you do not have bright aurorae washing out your sky periodically, you do NOT have optimal skies for viewing faint extended objects. You are in an area where light pollution, haze, etc is pervasive, and might want to think about lunar, solar, planetary observations, double stars, etc. There is lots of great stuff to look at, but don't expect to be knocked out by even M31 under crappy seeing conditions. In the northern hemisphere, if you do not easily see M31 naked-eye most times when you observe, you are in a less-than-good location. In northern Maine (especially with a dry Canadian high coming through) M31 is a beacon - you cannot fail to see it. The fact that it made #31 on Messier's list is probably a testiment to the poor quality of Paris' air when he made his observations.
     
    Last edited: Jul 26, 2005
  6. Jul 26, 2005 #5

    Chronos

    User Avatar
    Science Advisor
    Gold Member
    2015 Award

    Turbo is the resident expert on scopes here, earned by shear willpower in the face of winters' fury - or perhaps the cumulative effects of frostbite. I like short tubes, be they cat's or low f-ratio light buckets [my personal favorite]. They are portable, do not require bedrock mounts that weigh tons - and chicks dig deep sky views with wide relief angle eyepieces :smile: .
     
  7. Jul 26, 2005 #6
    well i got it to my friends condo who lives on the 19th floor of her building, and has a decent view of some stars and set it up. But the viewfinder is inverted. WHY? Also i was only given one eyepiece and i can't possibly see anything through it, the viewing hole on it is too damn small.
     
  8. Jul 26, 2005 #7

    turbo

    User Avatar
    Gold Member

    The viewfinder is inverted because that's the way simple refractors are. You can buy a Porro prism to correct the view, but that's not worth the money and it degrades the image in what is already a VERY tiny little instrument.

    Now to the eyepiece: You have an ocular that gives an unrealistically small exit pupil and probably an unrealistically high power (very common in small cheap scopes!).

    You need to know that you are dealing with department store trash, usually bought on impulse for kids by parents who have NO IDEA what they are doing. The buyers see beautiful full-color pictures of the Orion Nebula or the Andromeda Nebula (actually a galaxy), on the box and ASSUME that you can see this through a $100-200 telescope. This kind of marketing is a pet peeve of mine - it is nasty, cynical, and totally unethical. In a small-aperture scope, you cannot possibly see colors in faint extended objects, and in a cheap small-aperture scope you will be lucky to see the faint extended object at all.

    Get a decent pair of 7x50 binoculars (they can often be found on lawn sales fairly inexpensively) and look at the sky with BOTH eyes through a decent set of optics that will collect and properly focus more than twice as much light as a typical department store telescope. It will take your breath away. Now for a tip from LONG experience: If you can, try to buy a base-level pair of 7x50s from a company that sells really high-end optics. Their optical glass will be superior, their figuring will be superior, and their quality control will be top-notch. I have a pair of very basic Nikons that I got from LL Bean years ago, and they KILL.
     
  9. Jul 27, 2005 #8
    Thanks alot Turbo-1, I'm just gonna drop $400-$500 on a good telescope.
    What do you recommend, refractor or a reflecting telescope? I wanna view deep sky objects and photograph the planets. what camera would be good to use? My total budget for both will be around $800
     
  10. Jul 27, 2005 #9

    (Q)

    User Avatar

    Vincent

    What you're asking for would cost 5-10X what you're willing to spend. You can get an entry level scope and a few cheap eyepieces for that price, but that's about it.

    A decent cassegrain telescope will cost you about $1000 and is probably the best bang for buck for deep-sky and photography. A newtonian may a little cheaper but will be much larger,heavier and therefore more difficult to mount. You can get a small 80-100mm APO refractor for $400-$900 for the chinese scopes and a lot more money (many thousands) for larger aperture and better quality. The small APO take good pics but are only good for planetary and moon, they don't have the aperture for deep-sky.

    The most important thing about photography is the mount, and you'll be spending $1000 plus for a decent mount. Add more money for tracking, which you must have for photography, and a lot more money for GOTO capabilities, if you want the mount to find the objects for you.

    Then there are all the accessories that you didn't think about, which can run to equal or more than what I've already outlined. Some peoples eyepiece collections cost more than the scopes and mounts they own.

    Or, you can go all out and get a 28" truss dob with all the tracking and GOTO that will do all you ask for a mere $20,000.

    CCD cameras can cost anywhere from $100 (Celestron NexImage) to $10,000 and more. Or, you can get an adapter for your SLT or digital camera that mounts right to an eyepiece. Cheap, and not that effective.

    Check out Astromart, they are the largest website for buying and selling telescope gear, they also have a forum that you can read and sign up to ask questions.
     
  11. Jul 28, 2005 #10

    turbo

    User Avatar
    Gold Member

    For faint, extended objects like nebulae and galaxies, you will want as much aperture as possible, which should make you consider a Dobsonian, given your budget. For planetary observing, or double stars, a small refractor or catadioptric might be nice. Please be aware that for high magnification viewing or for photography, you will need a decent equatorial mount with a drive and that is not going to happen on your budget unless you stumble into a deal on the used market. You might want to seek out a local astronomy club, attend a meeting or two, and let the other members know that you are in the market for a scope. You might get a good deal that way, and you get to try it out first. Bonus!
     
  12. Jul 29, 2005 #11

    Chronos

    User Avatar
    Science Advisor
    Gold Member
    2015 Award

    I agree with Turbo. You will get more bang for the buck from a dobson in your price range. Actually, it's not terribly difficult to build your own mount. I buried a 4" pipe in the backyard to mount my first scope [it worked very well]. Portable mounts are a little more costly, but doable. The easiest way is to build a platform on wheels you can haul around in a truck or minivan. A little design ingenuity is all that's required.
     
  13. Aug 15, 2005 #12
    Is it possible for one to make his own telescope? I love making things. Any info on THAT?
     
  14. Aug 15, 2005 #13

    turbo

    User Avatar
    Gold Member

    It is not only possible but quite do-able. You might want to buy a dobsonian kit that supplies the primary and secondary mirrors and mounts and a focusser and build your own tube, rockerbox mount with lazy-susan base and pvc pivots.

    This will get you going pretty quickly. If you enjoy that experience, you might want to grind and figure your own primary mirror for your next telescope. You can buy mirrors to build a short focal-length light bucket, and if you decide to build another newtonian, you can grind and figure a long focal length primary for that. It's easier to figure a long focal length primary for a newtonian than a short focal length primary, and it will give you superior planetary views if you do a good job.
     
  15. Aug 15, 2005 #14
    Reason why i asked is becasue ther eis a guy down the street from me who makes them for a living and takes custom orders. I went to him and asked he could make me one tomy liking (based on that i can provide proper info) as to how i would like my telescope. Thank you turbo-1 you ar ea great help i am starting to like PF and thought i'd contribute a bit and doneate. :D
     
  16. Aug 15, 2005 #15

    turbo

    User Avatar
    Gold Member

    What kinds of telescopes does he make, and does he grind and figure his own optics? You may be able to get a really nice scope this way. It would be nice to know what his strengths are, so you can get the best bang for the buck. If he is a whiz at figuring mirrors for newtonians, that gives us a nice starting point. Knowing this, we can figure out whether you want a large-aperture dobsonian, a long-focal length planetary newtonian with curved spider vanes and a small secondary (great for planetary views), or maybe something in between.

    If he buys optical components and assembles optical tube assemblies and mounts, that's another level of competence (one which you may be able to approach with a decent Dobsonian kit).

    Let me know what he usually builds, and I'll try to help you get a decent scope. By the way, I have some massive copier lenses that might make good objectives for short focal length (but big aperture) finders. Once you figure out what kind of scope you want to build or buy, let's figure out what kind of finderscope (or low-power second scope) you might want to have, and I'll send you an objective to build that with.
     
  17. Aug 16, 2005 #16
    Well i just spoke to him on my lunch hour, and he said he doesn't like to do it too much now, but it can be a possibility. I forgot to ask him what kind of scopes he can build but he does grind and figure his own optics, his shop is quite old and dusty and he is an older man in his 70's i can tell he knows his stuff. anyways he has a bushnell dobsonian telescope (114mm) that he can sell me for $150. It has a bulb-ish base and is moved fairly easy. i suck at words sometimes, so it's hard for me to go into detail on how this scope looks but i'm sure you get the idea
     
  18. Aug 16, 2005 #17

    turbo

    User Avatar
    Gold Member

    It sounds like the Bushnell might be the same scope that Edmunds Scientific calls the Astro-scan. Is this it? They're $200 new with a couple of eyepieces.

    http://www.scientificsonline.com/product.asp_Q_pn_E_3002001

    You might want to join a local astronomy club, or at least go to a meeting or two as a prospective member and see what telescopes the other members have outgrown or no longer have the space to store. You might get a REAL deal that way.
     
  19. Aug 16, 2005 #18
    i think so, but i don't know of any links, or clubs here in seattle. Maybe you can provide a linky or two?
     
  20. Aug 16, 2005 #19

    turbo

    User Avatar
    Gold Member

    OK, but it isn't that hard to type "astronomy club" and Seattle into Google. (teach a man to fish.....)

    http://www.seattleastro.org/

    There are LOTS of clubs in Washington state.
     
  21. Aug 16, 2005 #20
    well, i know, but...just wasn't sure i never had been to a star part/club. but thank you that link rocked and i printed the 16page pdf.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Telescope lens upgrade
  1. Lens cleaning (Replies: 0)

  2. Luneburg lens (Replies: 5)

  3. Muons and telescopes (Replies: 4)

  4. Gravitational lens (Replies: 1)

  5. Telescopes (Basics) (Replies: 15)

Loading...