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."

Comments

Astronomy software

[jchillerup]

The first thing I'd do would be to install Stellarium. That'd enable you to "tune in" on stars, even in cloudy weather.

Re:Astronomy software

[Mr2cents]

While we're listing astronomy software: Kstars is great too.

And if you want to use a (web)cam on your telescope, take a look at registax.

Re:Astronomy software

[screen404]

I have been doing backyard astronomy for a few years now.

Hear is the list of groups and websites you want to visit or sign up:
http://tech.groups.yahoo.com/group/DeepSkyImager/?yguid=222412370
http://tech.groups.yahoo.com/group/ETXASTRO/?yguid=222412370
http://tech.groups.yahoo.com/group/astroplanner/?yguid=222412370
http://www.weasner.com/etx

The software. One of the best softwares i have tried is Astroplanner http://www.ilangainc.com/astroplanner/
It allows you to plan your observations or download plans of others.
Will control your telescope and help align it correctly. runs both on Mac and PC.
They guy is very good at support, and it is not very expensive.

ps: I'm associated with Astroplanner but a very happy user.

Re:Astronomy software

[Rei]

The Weasner site would, of course, only be particularly useful if they're buying a Meade. As a Meade owner myself, however, it's wonderful ;)

Anyways, to the poster: First off, let me recite the standard advice for getting a telescope:

1) Don't buy from a "junk" brand (and there are a lot of them -- Bushnell, Tasco, Baytronix, etc). Get a name brand -- Meade, Celestron, Orion, etc.
2) Get large aperture, but keep the telescope portable, or you'll never use it.
3) Don't buy from Ebay.
4) Don't even buy from a store like Walmart. Buy from a telescope dealer.
5) Get quality optics like Televues and Naglers.
6) Subscribe to astronomy magazines, join a local astronomy club, and on and on.
7) If you can't afford everything above, just buy binocs.
8) Don't do astrophotography; you'll just be disappointed.

Let me tell you that most of that advice is bollocks.

Follow #1 and, as money allows, #2. Completely ignore the Ebay advice. Ebay is *wonderful* for telescopes and accessories (of course, verify that they're actually cheaper there than elsewhere before you buy, but they usually are). I find that things get to you faster from Ebay, too, and they're almost never "backordered" like so many stores are. I bought my scope, four eyepieces, and a barlow from Ebay, and everything was exactly as described, shipped quickly. One caveat: With the scope itself, if it has a motorized mount or an autostar, make sure you have a warranty. This is very sensitive scientific equipment, so Murphy's Law applies. Also, never trust an airline with *any* part of your scope any further than you can throw them, no matter how well you pad it. Trust me on this one. I've had an equatorial mount sheared clean in half by them -- i.e., straight through a bolt with about half an inch of steel, sheared right off. I think they were having a monster truck rally on top of my luggage. If you're taking a scope on the plane, the whole thing must be carryon. Let me also take this change to plug Meade's customer service, which I've dealt with several times, and have been *very* pleased with.

The "Televue and Nagler" advice is idiotic. People who advise that (and I've heard way too many) would have you spend your entire budget on two eyepieces. There are plenty of cheaper eyepieces that aren't too much lower quality than those top-of-the-line pieces. Antares eyepieces are good. I use Meade 4000 series, and have been very happy with them. On ebay, you'll only spend about $40 each for them.

Your budget is bigger than mine was, so I wouldn't recommend my scope (a Meade DS 2130AT -- a 5" newtonian with a motorized equatorial mount and autostar -- $170, plus some money for eyepieces to replace the junk ones that it comes with). You can do better than 5" aperture. I wouldn't go with a newt at all; they'll get too heavy and bulky as they scale up, and the short tube newts aren't that good. I think you'd want one of the Cassegrain or Maksutov varieties so that it'd be more portable. Perhaps something in the Meade LX series.

It doesn't hurt to join clubs or subscribe to magazines. On the other hand, you don't *have* to. There are plenty of astronomy forums online, and lots of articles.

As for astrophotography, it's not a case of "don't do it", just "do it right and be patient". One thing not to do, IMHO, is afocal with your current camera. On sites that list afocal as a method, caveats with it often are not stressed enough. If you have a fast lens, the vignetting will be atrocious, often to the point of the pictures hardly being usable. Also, the higher the magnification you use, the worse the vignetting. You really need a camera that you can remove the lens on (eyepiece projection and prime focus astrophotography). Ignore the people who say to get an SLR (non-digital). If you want to use a regular camera, get a DSLR; modern astrophotography benefits hugely from digital postprocessing. However, any camera that might be even a little heavy should

Web site

[tumutbound]

Have a look at http://iceinspace.com.au/ while it's run out of Australia, there are members worldwide.
'Where to start' is a common question there.

Well there's always...

[Artaxs]

... Google Sky.

Try building a telescope

[Derwood5555]

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.

get an Apochromatic Refractor

[Janek Kozicki]

$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 .

Re:get an Apochromatic Refractor

[Phroon]

$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.

You seem uninformed on the caveats of refractor vs. reflector designs. You have the basic ideas right, but your reasoning is a bit flawed, let me try. Refractors are a lensed design, the problem with lenses is that they do not bend all colors the same amount, that is their refractive index varies by wavelength. To correct this most telescopes use a achromatic doublet, which converges most colors except for the near purple end of the spectrum, resulting in a purple haze around the object your viewing. Recently the concept of an apochromatic has reached the consumer, in which a doublet or triplet with exotic glasses are used to focus much more of the visible spectrum than achromatic reflectors. This results in a perfect image with no obstructions in the objective (I'll get to this in a moment). However, the exotic glasses are extremely expensive, resulting in a small aperture for the money.

Reflectors, by contrast, are a mirrored design. Mirrors bend all light the same amount, so they do not have the chromatic problems. The issue with reflectors is that the secondary mirror has to be in the path of the light that hits the primary mirror, so there is a "shadow" of the secondary mirror and it's supports on the primary mirror. This does not create a hole in the image, but the secondary and it's supports do diffract light around them, resulting in stars that have a spike around them. The Hubble is a reflector design, and shares these diffraction spikes. Reflectors also suffer from coma distortion.

What it comes down to then is Aperture vs Obstructions. Aperture (the size of the primary focusing element): Reflectors have much larger apertures than similarly priced refractors. A higher aperture allows you to see darker of objects, it allows you to use a higher magnification and increases how much detail is present at higher magnifications.
Obstructions: These lower the amount of light getting to the primary mirror and cause diffraction in the image. The reduction in light is acceptable for reflectors as they have a large unobstructed aperture. The issue is diffraction with bright objects, mainly planets and stars. For stars, it simply causes a starburst pattern in the image, but for planets the diffraction of the circular secondary becomes important because planets are extended objects with details. With stars this circular diffraction simply increases the brightness of the sky surrounding the star, but for planets this slightly blurs the image of the planet which some feel is unacceptable.

The telescopes you've listed are in the $10,000 and above range, very far above the poster's $1000 budget. I couldn't even find a mounted 80mm semi-apo (the minimum aperture I'd suggest for planetary viewing, let alone deep sky) for under $1000. For sub-$1000, a reflector wins over a refractor hands down simply because there are no apos in this price range. The aperture of a reflector simply destroys the possible advantages an refractor in this range due to the chromatic aberration on planets, plus you can do deep sky observing with a sub-$1000 reflector and still be happy with the planets you can see.

Budget too small

[Cecil]

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.

Re:Budget too small

[dargaud]

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. I'm not sure if this really applies anymore. Nowadays with a digital SLR attached you can take short exposures (just a few minutes) where the defects in alignment and stability won't show, and then stack the images in software. As an introduction to astrophoto it beats blowing thousands on an arch-stable mount.

Re:Why not binoculars first?

[Starwanderer]

Yes, entry level. A lot of amateur astronomers have ground their own mirror for their first telescope. It's not a difficult thing to do at all, although I'm sure it might sound as if it would be to someone who hasn't done it.

I went through the same thing

[Phroon]

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.

Re:A Great Camera?

[Registered Coward v2]

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.

Re:Why not binoculars first?

[Lumpy]

You can get a quality scope that will WOW you for far less than that. Orion Skyquest X10 classic. 10" Dobsonian that blows away everyone that looks in it for $550. Go up to 12" and kick the crud out of almost all Cassegrain scopes for $870 and get something that can blind you by looking at the moon! it has fantastic quality all over it. and YES I have taken photographs with it. no not long exposure but then that's advanced and not entry level like the question asked.

For a grand I can set someone up for basic entry level easily out of an orion catalog. That is where he needs to start. and he also needs to stay away from anything smaller than 8" primary mirror size.

Oh if it's a refractor telescope, dont touch it. Short of professional 6 figure versions I never looked through a refractor scope that was worth it's weight in scrap aluminum.

Good binoculars, star charts, and a red flashlight

[mikehoskins]

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.

Re:Good binoculars, star charts, and a red flashli

[dumb_jedi]

I'm an amateur astronomer myself and Mike's advice is perfect. Astrophotography is addicitive, but needs planning and patience. As I assume you don't own an telescope yet, my advice is to buy a good binocular. If you still want to buy an telescope, buy a cheap ( not cheapo ) one, around US$ 250, with EQUATORIAL mount, that's VERY important. Get used to it, learn what you like the most to observe ( deep-sky objects, planets, moon, variable stars, nebula ), learn how to align your telescope so it can track the sky movement's. Then borrow from someone an old SLR camera, with film. Yes, that's right, not a digital one. Couple in your telescope ( you'll need an adapter ) and read some FAQs, ask help from your astronomy club and play with the settings, see how they change the result. You can use a webcam for that too, and some software like Registrax to stack the pictures, the result is amazing! After you get to know the dirty details, you'll know what's the best equipment to buy, the best DSLR camera. One tip: it's not about the camera or the telescope. I've seen AMAZING pictures taken with an old SLR with a home-made refractor telescope, mounted on a US$ 500 mount. It's about the MOUNT, spare no expense here. Spend 1000 on a mount and 200 on a telescope, you'll get GREAT pictures. Dark skies for you!

Re:Good binoculars, star charts, and a red flashli

[OwnedByTwoCats]

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.