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Got my first telescope!

  1. Aug 24, 2015 #1
    Over the last year or so I've been thinking seriously about getting a telescope, having my eye on the Celestron Nexstar 6SE model or getting a slightly smaller 5" model that's more automated for about the same price.

    Well, yesterday my mind got made up for me as it was my birthday & my wife got me a Celestron Sky Prodigy 130 like this one. She said I could exchange it for another if I had something else in mind, I briefly considered perhaps the 6" model but I think the 130 should suffice nicely and the automation feature is probably good for a newbie like myself.

    The main reason she picked this one was that she was under the impression that I I could combine my photography hobby with this one, because it has a built in digital camera. However it turns out the digital camera it has is used for alignment purposes only, not for astrophotography, so I think she was a little mislead by the "built in digital camera" in the advertising.

    Anyway, brings me to (one of ) my question(s)

    I'm see there is a camera attachment from Celestron available here, would this be sufficient for getting started in astrophotography? If not - what would be?

    After unboxing yesterday I was aiming it across the lake from where I live and expected the image to be inverted, but it's inverted with about a 30 degree tilt. I could find nothing in the manual about terrestrial viewing, do I need to get a different eyepiece or adapter for terrestrial use?

    thanks in advance.
     
  2. jcsd
  3. Aug 24, 2015 #2
    The angle is due to the relative position of the eyepiece on the tube. If the tube can be rotated such that the eyepiece is at the very top then the image would be 0 degrees (but still inverted). A bit awkard to look through and you may need a step to stand on. Or rotate it 90 degrees such that the eyepiece comes off at the side... then the image would be OK as well. Not much can be done about that.

    It's been a while since I played with reflectors so I may be wrong at one or the other position. With a wedge eyepiece adaptor you may be able to 'right' the image further.

    If you can mount a small webcam on the eyepiece it can be rotated to compensate.
     
    Last edited: Aug 24, 2015
  4. Aug 24, 2015 #3

    Andy Resnick

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    I think that's probably an excellent starting scope- have fun! As for your camera insert, that should also be just fine for starting out.
     
  5. Aug 25, 2015 #4
    The traditional way to do terrestrial observing through a Newtonian is to aim the scope and then turn your back on the object before you put your eye to the eyepiece. You might still have to tip your head a little to get it perfect. You can get image erectors, but why bother when it's this simple?
     
  6. Aug 27, 2015 #5

    Chronos

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    You have a fine and practical scope there, even if it isnt capable of 'Hubble quality' photographs.
     
  7. Aug 27, 2015 #6

    davenn

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    lucky you, that's awesome and a great scope to get started into astronomy. Beware tho .... as you grow in the hobby, aperture fever will strike you :smile:
    and there will be this ongoing urge to get scopes with larger apertures.
    In reality, tho it's nice to have a 12 or 14 inch mirror scope. The real ideal max size, for most serious amateur astronomers, is around the 8 - 10 inch diameter mirror
    its the good trade-off for having a scope that is still reasonably transportable in the avg family car :smile:

    looking forward to hearing and seeing your exploits as time goes by

    Am going to suggest to you what I told another new astronomer earlier today.
    Get into the habit of doing a observing diary. Do it for EVERY time you purposely go out under the stars
    be it to do unaided looking around, say for meteors or with binoculars or with the scope
    Its great to have a diary to refer back to as the years go by and say compare observations with earlier scopes with the latest and greatest scope you have

    a couple of excerpts from my one ( NOTE the tabs formatting was lost copying and pasting to the forum)
    your ideas for layout will probably be different :wink: ..... I just use a word doc file


    2005
    Date Time (EST)

    Object Constell. Comments
    July 2005
    From Home

    03 1600

    Sun Many spots visible clear umbral and penumbral regions visible

    1830-1900

    Jupiter 2 moons, 4 belts visible good viewing overhead
    Mercury low in West a bit fuzzy
    Venus low in West, bit fuzzy, looked gibbous phase
    Omega Cent Glob; Ex.Brt, clear easily resolved
    NGC6121/M4 Glob; Just resolvable
    NGC6475/M7 Op Cl;

    2015-2100

    NGC6405/M6 Op Cl;
    NGC6388 Glob; Mag6.7, Just resolvable, small, compact
    NGC6514/M20 Trifid Nebula; Fnt, just visible
    NGC6531/M21 Op Cl; Brt

    --------------

    2013


    Jan. 04 … got the CPC925 out to see if I could see Comet C/2012 K5 (LINEAR)
    I was out the nite before with binoculars and thought I had found it
    But using the scope tonite, I found I had been looking at M37 and or M36
    A couple of faint fuzzy open clusters that the binoculars couldn’t resolve
    into individual stars but the scope did.

    After 2 hours of searching, I finally found it at the location it should be.
    This comet was definitely not visible in binoculars as had been reported. It was a very faint fuzzy blob in the scope with a 40mm eyepiece.
    Estimated magnitude at ~ 9.5 – 10.
    Jupiter also looked really good during this time

    May 10 … Partial Solar eclipse. Viewed and Photo'ed from Thornleigh

    Aug 16–20 Nova Delphini. The nova appeared with a magnitude 6.8 when it was discovered and peaked at magnitude 4.3 on 16 August.
    Viewed from home and from Bobbinhead Rd, jst N of Sydney. Photo’ed from Bobbinhead Rd,


    cheers
    Dave
     
  8. Aug 28, 2015 #7

    Chronos

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    Adding to dave's post, most people find anything over about 10" to be a beast. The damn mount is like a national monument. And the scope is so jittery without a massive mount it is nearly useless. So don't let aperature fever overcome your good sense. If you have a permanent observatory I may concede a few inches.
     
  9. Aug 28, 2015 #8

    Andy Resnick

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    In addition to size/weight constraints, if the user is located in a place with poor 'seeing' (say, Cleveland OH) there's not much point in a large aperture- I would get slightly brighter fuzzy blobs, but no additional resolution.
     
  10. Aug 28, 2015 #9

    davenn

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    but if you are going to go big, one day make it worthwhile 30", f5 :wink:

    from the recent Queensland Astrofest (Star party)

    Terry Lovejoy ( of Comet Lovejoy fame -- earlier this year) took this pic of his friend Renato Langersek.and his scope

    big scope.jpg
     
  11. Aug 30, 2015 #10

    Chronos

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    Missing the lift chair.
     
  12. Aug 31, 2015 #11

    Andy Resnick

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    He needs a second one for his other eye.
     
  13. Sep 17, 2015 #12
    Thanks for all the great replies, suggestions & advice everyone - it's been awhile since I visited this board and I forgot about this post!

    I've managed to get the telescope out twice since the post, one night I set it up, just used manual control & got some good looks at the waxing gibbous moon in its later phases, then I went on vacation and the weather has been crappy but I managed to get it out last weekend on a clear night and try the built in computer functions.

    Where I live I'm surrounded by mostly deciduous forest on each side, so I took it out on my back north facing deck to see if the align feature would work. My house is a two storey so I was pretty well restricted to a straight north view. I pressed the align button anyway, and it took awhile and read it wasn't able to find stars once or twice, but it eventually finished. I then pointed it at Polaris and it showed a bright star not quite in the centre of the view, I adjusted it manually to center it, then had it find the Andromeda galaxy and it found (what I'm pretty sure is) that too, again just a bit off centre. I was using the 9mm eyepiece only because I forgot where I put the 25mm one, but I could see a fuzzy glob of stars, I wasn't sure if I should be able to see the galaxy arms or not.

    For the targets not being centered I'm not sure of it's a camera calibration issue or not.

    One thing I don't like is the big bulky D cell battery pack that powers the motors, I actually dropped it by accident the first use and broke the wire off and had to solder it back. I think I may have found a better solution though, I fly RC planes and multicopters and a lot of this flying is FPV so I already had a barrel connector (the same size as the one on the batter back) for my 19" TV modified with a lipo battery connector so I can power the TV for remote viewing with one of my 3 cell 12V LiPo batteries. I have a lot of these batteries so I'll just put a square of velcro on the telescope mount somewhere then I can attach a small 12v LiPo to it and save a ton of weight and not have to worry about wrapping the cord etc.

    As for cameras, I'm wondering if it's worth my while spending a few more bucks to get this one, or this one - instead of this one - thoughts?
     
  14. Sep 17, 2015 #13

    ogg

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    Glenstr: your links result in "Parameter 'out' is required." There are myriad ways to approach a new hobby. My hobby is dabbling. I'm not an amateur astronomer/sky watcher, so there's gotta be millions of people more knowledgeable...Anyway, chances are you are going to want a mobile telescope. The bigger it is, the less mobile it is. The more expensive it is, the less you'll want to toss it in the back of the car and take off. (OMG, if that doesn't sound scary, both for breaking the scope, and for theft issues, then you don't live on the same planet as I do). So while you may have a place for setting up the scope near-by, you need to consider more than just simply what "the best" camera is. IMHO, 21st century astronomy isn't about visual sighting, its about video capture. Having a "retro" scope is ok. (Do you also use "box" cameras?) What you spend your time doing is up to you. As you probably know, eyeball astronomy is (virtually all) "black and white". To get the color, you need time and so you need a digital scope. Depending on your expendable income, you may choose to go whole hog into a hobby before you actually know if its for you. There's lots of used equipment out there that attest to that. Which suggests a more cautious approach (buy used). But yeah, new is definitely more sexy than "preowned". As I mentioned, your links lead to dead ends for me, not sure if its my issue on this site or the site's policies, I usually run into the same problem here.
    Oh, two more comments, and again, take them for what they're worth:
    If you don't have stellarium on your PC, get it (or similar, Stellarium is free, and fantastic, imho)
    The considerations of astronomy rapidly diverge from terrestrial photography. One set up probably will have too many compromises for anyone serious about either. As a beginner, you will quickly figure this out.
    Last time (several years ago) I priced out what I thought a minimum system (astronomy) system would cost (for me) it was between 3k-4k US$, fwiw. But ymmv and again its not about getting the best, its about growing into it so you can have fun and be pleased with what you're doing with it. You'll not get (astronomical) shots to equal Hubble's anytime soon, LOL. Any I do think that photographs would make a fantasitc scrap-book. (Digital, or even hard copy). Often the progression is Lunar, Planetary, Stellar, then extragalactic, but that's arbitrary...
     
    Last edited: Sep 17, 2015
  15. Sep 17, 2015 #14

    davenn

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    ALWAYS pick the 3 brightest stars you can see. If you happened to pic fainter stars, that would be a good reason it took so long to get an alignment

    most likely was your not quite getting the alignment stars dead centre in the view as you did your alignment process

    The other good probability was that you didn't have your mount well levelled before starting your alignment process
    this can really throw things out

    doing that adjustment would have thrown your alignment out ... if your 3 star alignment was done correctly, Polaris WONT be dead centre, Polaris isn't exactly right on the pole

    Do your 3 star alignment again


    yup LiPO's are much smaller for the equiv amount of power

    for something more than just planets, the first one would be the best start for you and is quite reasonably priced as an intro camera
    The other 2 are primarily planetary/Lunar cameras and are not likely to perform overly well on deep space objects


    cheers
    Dave
     
  16. Sep 18, 2015 #15
    Thanks - this particular telescope has an auto align, where you just press the align button and it will automatically search the sky until it finds enough stars to get its bearing. I did some more reading on it and found that it's best to have it aimed at a clear section of sky (likely aimed at a bright star, as you suggest) as far left as possible, as it will skew to the right in its search. The first time I let it auto align I did not do that.
     
  17. Sep 18, 2015 #16

    davenn

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    ahhh ok
    to be honest, am not a fan of the total auto align, hence why I use the semi-manual 3 star align
    where it asks you to point to a star, it ackn's that then the next and the next. Then it does its
    calculations and works out where it is

    my scope, also a Celestron with the Al/Az mount and hand controller
    it mite be worth trying a 3 star align :smile:
    As I commented, adjusting alignment to get Polaris centred would have put the alignment out

    keep posting in this thread as you progress and let us know how you are getting on. Anything I can do to help, I will

    cheers
    Dave
     
  18. Sep 18, 2015 #17
    Thanks for the suggestions, I plan on trying the manual aligning too, might work better with limited sky as well.

    Another thing I just thought of - unless I'm mistaken this telescope also tracks the stars, in that it will keep them in view & correct for the earths rotation. I'm thinking I should be able to fashion a mount somehow for a camera (where there's room), for example my Sony Nex 5 or A5100, and use it for longer exposures of the Milky Way etc.?
     
  19. Sep 18, 2015 #18

    davenn

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    yes, this is correct, its the whole point of doing the alignment. BUT there is a huge caveat ( limitation)
    There's something you may not have heard about called field rotation and this is not a problem for visual observing BUT is
    a problem for doing long exposures, anything over around 30 secs

    Field rotation is what happens to the object as seen through the scope, where the field of view rotates.
    This happens because the scope isn't tracking the true motion of the star/object across the sky.
    Stars and other deep space objects move in an arc across the sky rather than straight lines and
    because of the Altitude / azimuth tracking of the scope it tracks the star/object in a series of small steps
    rather than a smooth arc

    will let you digest that whilst I draw a diagram to add to the text .....
     
  20. Sep 18, 2015 #19

    davenn

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    OK ....
    star trail arcs ....

    star-trails-26.jpg

    star-trails-25.jpg

    Al/Az tracking..... rough drawing

    track.GIF

    to track stars in a smooth arc, a different type of mount is used called an EQUATORIAL mount
    This type of mount is aligned to the north or south celestial pole ( depending on if you live in the nthrn or sthrn hemisphere)

    See that top pic and how everything is rotating around a central point ? that star near the centre ... yes, Polaris .... one of the scope's axis is aligned to the pole and the other axis will then track the true star motion across the sky



    Dave
     
    Last edited: Sep 19, 2015
  21. Sep 19, 2015 #20

    Drakkith

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    It's unlikely that particular mount will place every target near-dead center every time. My $1400 mount I use for astrophotography doesn't even center targets that well. (Which sucks for imaging)

    Based purely off of a quick look at the specs for each, and no experience using any of them, I'd probably go with the middle one. The large sensor will make it easier to find your targets and having more pixels gives you more options than having fewer. Trust me, trying to find your target using a tiny sensor is extremely frustrating. One thing I'd do before purchasing is make sure you can still get a color image while the camera is binned 2x2 or 4x4.

    Note that all three are designed solely for planetary/solar imaging. They will not work well for deep sky imaging of galaxies and nebulae.
     
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