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Entry-Level Astronomy?
brobak writes "I'm getting ready to move into a new home on a couple of acres of rural property a significant distance from any large source of light pollution. I've always been interested in astronomy in general, and I would like to put my dark skies to use by picking up decent telescope and learning a bit about the skies over my head. The overall budget for this project is going to be around $1,000. I am particularly interested in astrophotography, but I understand that that may carry me outside the scope of the initial budget. I've already signed up for my local astronomy club's next monthly meeting. I have been doing Web research, but I thought that the Slashdot community would be the perfect place to get opinions on entry-level equipment, websites, and books."
The first thing I'd do would be to install Stellarium. That'd enable you to "tune in" on stars, even in cloudy weather.
... Google Sky.
Militant Agnostic: "I don't know, and damn it, neither do you!"
When you go to your astronomy club's meeting, see if they have a group that builds telescopes. Building your own telescope is a great way to save a lot of money, plus you'll learn a lot in the process.
If you're lucky enough to be in the SF bay area, the Chabot Observatory Telescope Maker's Workshop is a great place to learn about telescopes, and also how to build them. They can guide you through the process, and its really not as hard as you might think. http://chabotspace.org/vsc/observatory/telescopemakers/
If you want to hold of on astrophotograpy for a while, I recommend picking up a Dobsonian mount telescope. They're a low cost design, and you can find 10 and 12 inch reflectors for $800. Also, they're easy to build, which goes back to the building your own comment earlier.
Dobsonians are not suitable for photography though. But, they are a cheap way to break into backyard astronomy.
$1000 is not much. I've been doing research quite a long time on what should I buy, to get the best possible view both for planets and deep-sky. You know - usually for deeps skies a newton with huge mirrors is good, while they are not applicable for planets, because newtons cannot produce big magnification with enough detail. While for planet viewing the refractors are the best, because they can produce big magnifications without the distortions of newtonians. But refractors have too small aperture to collect enough light for comfortable deep-sky viewing.
The best balance in this big_mirror/refractor conflict is an apochromatic refractor. Because - apochromatic means that the lens are covered with special layers that give about 96+% of light transmission (so it's better than non-apochromatic refractor, where some light is wasted on the lens and you don't see deep-sky objects clearly), and special layer eliminates light dispersion like in an optical prism (otherwise each color would go on a different path and the resulting picture of something looked more like a rainbow instead of beight sharp). And also as a refractor it's good for planets. But... this APO refractor has to have big aperture, or it won't work for deep-sky anyway.
Refractors have some other advantages - for instance you don't have unnecessary air flow between the lens because they are inside a tube. Newtons are much brighter (good for deep-sky) but air turbulence blurries the view on planets.
Oh, and forget about cassegrains, they are compact, that's true (the only advantage). But the view is terrible.
Well if you have just $1000 you gotta decide: (1) want to see distant galaxies (newton), or (2) view to see planets (refractor). But I suggest to spend a bit more cash and get APO refractor. Should be good for both.
You can look at those reviews I had bookmarked long time ago: http://www.cloudynights.com/item.php?item_id=1260 and http://www.cloudynights.com/item.php?item_id=32&pr=2x6x17
You can consider Takahashi also, althought from my research it looks like TMB make better equipment, but you never know that for sure: http://www.tmboptical.com/itemsGrid.asp?cat_id=4 .
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You're not going to have enough budget to pull off any sort of astrophotography that will satisfy you, so I would recommend you start saving up.
:)
For astrophotography you absolutely *must* have an equatorial mount, it is simply impossible to do astrophotography with a stock altitude-azimuth mount, because while it can still track the sky as it moves, the view will rotate as it does so. With an equatorial mount, the view stays properly aligned even while it tracks the sky. German equatorial mount is the preferred mount for astrophotography. Even looking at just the mount you've pretty much blown your budget right there.
Secondly, you're going to want a high quality right-ascension drive motor. It's possible to get by without one, though tedious and limiting, but don't bother with a cheap one. The gearing is insufficient for astrophotography and will cause jerking and backlash resulting in awful pictures.
You'll also need to get a heavy duty mount and tripod, because a normal tripod is only designed for the weight of a telescope, not a telescope with a camera hanging off the end. You also need to make sure you've got a very sturdy, firm mount, because any vibration at all will ruin your pictures. Remember we're talking about huge magnifications and long exposures here, it's extremely easy to blur the pictures. Astrophotography is a challenging enough hobby to begin with. Inferior equipment can make it damn near impossible.
You'll notice I haven't even talked about the actual telescope yet. That's how important the mount and tripod is to astrophotography. So now that I've completely blown your budget, I'll try and be a bit more gentle on the telescope side of things. Probably the most bang for your buck in this case will be a newtonian reflector telescope. They're by far the cheapest type of scope per inch of aperture. Sort of big and unwieldy, and they require very precise and regular maintenance (called collimation). I'd recommend a bare minimum of 5" aperture, but as high as 8" if you can manage it.
Then you have to figure out how to mount your camera to the telescope, which is a black art in and of itself. Duct tape is not recommended. For most SLRs and telescope brands you can find a suitable T-mount adaptor which will allow you to attach your camera in place of the telescope's eyepiece. For non-SLRs, I'm not sure. If you were thinking of getting an actual astronomy CCD camera (such as the popular SBIG brand) well that alone will blow your budget and then a whole lot more. Then you'll want a second one to use it as an autoguider.
Astronomy isn't cheap, but it is rewarding. Good luck and clear skies.
Random and weird software I've written.
I went through the same thing. I was fresh to amateur astronomy and didn't know what to do. My first warning: Don't spend to little on a telescope. $180 for a StarBlast is the lowest I'd pay for anything decent (and it is, I drool over it as a quick 'plop down and observe' scope from time to time). Second Warning: Astrophotography is insanely expensive. As in 10+ times your budget. Don't do it. If you really want to do astrophotography take a camera, put it on a tripod, point at the sky, set it as wide as you can and expose for 15 seconds for digital, a few hours for film. The results are quite nice.
Here's what my own experiences have taught me: Get a Dobsonian. With $1000 you can get a 10"-12" Dobsonian and still have tons of room for accessories. A dobsonian is very portable compared to a refractor and with near zero setup and takedown using it is much easier than a refractor too. 10" is a lot of aperture and you won't catch the "aperture fever" for something bigger for a while. The scope I eventually got is an Orion XT10 Intelliscope, but you may not want the computerization with your budget.
I found the people at Cloudy Nights very, very helpful. They have reviews of lots of products as well as their forums and they tend to specialize in getting the most out of your money.
As far as books go, I use Nightwatch by Terence Dickinson every night I observe just for the charts. Star Watch by Philip Harrington goes well with Nightwatch as good place to find new objects for the beginner. A lot of people suggest Turn Left at Orion, but I fount it to be a bit slow and the charts lacking in lower magnitude stars for their size.
Personally, if I had the kind of space you had, with no light pollution, and if I had the budget you mentioned: I would buy a high quality digital SLR camera. Obviously, if you're looking to photograph things that you need a telescope to see, this wouldn't be a good use of money for you. But, if you're looking to take shots of constellations and the moon and such, then a high-quality digital SLR with a tripod will work beautifully.
A good dSLR can be had for under $500 (Canon 350d/d40) new or even less used (KEH.com and fredmiranda.com (Buy & Sell forum) are good sources) and quality tripods start at $100.
That leaves the choice of lens - whatever you buy if you decide to go the camera / tripod route invest in a really good lens - it's better to buy a $300 body and a $700 lens then vice versa since your glass has a greater impact on picture quality than MP's and you'll want fast glass (the ability to shot at faster shutter speeds in low light). Your investment will pay off over time since the lens will stay with you when you get a new body. Don't get all wrapped up in MP - anything 6mp or above is more than adequate for virtually any shoot. Don't worry about the endless Canon / Nikon fanboy debates - both are great systems so pick one that you like, meets your needs and fits your budget; realizing that you investment in lens will pretty much result in a lock to one manufacturer.
I'd recommend holding of on a purchase until you attend a club meeting or too - you'll get advice there as well as a chance to talk about what you want to do and learn about other's rigs before you invest.
I'm a consultant - I convert gibberish into cash-flow.
I read in an astronomy magazine that a budding astronomer should first buy a high powered pair of binoculars (10mm x 50mm) and star charts, plus a red LED flashlight.
That way, you get used to pointing out where things are in constellations. You also find out if you can handle the long nights, getting your eyes used to darkness and waiting, waiting, waiting.
It takes about an hour to get used to the darkness. Red LED flashlights also keep your eyes dilated, having little effect on night vision.
If you get good at doing things the "old-fashioned way", then buy from somebody on EBay, who spent the big bucks and found out they weren't as interested as they originally thought.
Worst case, you got a good pair of binoculars and saved about a grand.
Best case, you learned a lot more about astronomy and will be able to find anything by constellation.
Of course, download and use Stellarium. They have a red night vision mode you can take with you on a laptop. (I'd still recommend dimming the display as much as possible and enabling a 1 minute monitor shutdown, to keep your eyes).
Also, go to http://heavens-above.com/ for more information about tracking objects in the sky. (Be sure to synchronize your clock to the atomic clock, since satellites and other objects wait for nobody). Watching satellites pass is a good way to keep yourself interested in astronomy, while you wait, wait, wait.
Heavens-above.com and Stellarium are excellent planning tools, as are your handy star charts.
One of my earliest astronomical memories (aside from the shows at the local planetarium) was standing on a friend's driveway just after dusk. He says to me, pointing at a bright point of light against the rapidly darkening sky, "hey, I bet that's Saturn". He ducks into the garage, and drags out a 8-ish inch reflector telescope his dad had made. He lines it up, adjusts the focus, looks, and then invites me to have a look. Boom, there it is. Just like in all the picture books, only live, in front of my eyes.
So look at the planets through your scope. It should be bright enough to resolve any of the naked-eye visible planets as discs. You should be able to see the phases of Venus.
On my desk I have a picture of Comet Hale-Bopp. I took it with a 35mm film camera, with a 100-200 mm zoom lens set all the way out. Tripod, Kodacolor Gold color film (although there isn't any color in the print.) I thought I would want to take more astro-photographs, but haven't gotten around to it yet.