Advice on telescope

[kookbreaker]

Also, what telescope you buy depends on where you are and where you plan to use it.

In the heart of a city, there is not much use for a really large telescope because the light pollution washes out so much.

Don't be to sure about that.

 

[Wangler]

I'll third the suggestion to start with a good pair of binoculars. At least 50mm, bigger is better (will gather more light and let you see fainter objects). The second number divided by the first number should optimally be about 7 for nighttime viewing.

Remember that larger objectives mean a heavier binocular; 50mm might be at the limit of extended viewing comfort for many folks.

Also, there are few who live in dark enough locales to truly allow for the pupils to full dilate to the 7mm maximum (average) to which you refer.

Most are better off with binocular exit pupils of around 5-6mm, especially those of us in suburban locations.

If you are looking through a 7x50 binocular (which has a ~7mm exit pupil) from a bright suburban location where your eye only dilates to 5mm, you are only using 35mm of the objective lens..might as well use a lighter (and cheaper ) 7x35 pair of binoculars in that case.

Also, the older you get, the less maximum pupil dilation your eye can achieve.

 

[Humanzee]

If you think binoculars might be the way to go...and the views are nice...do consider a nice tripod with a mount to hold them. A good astronomy binocular can be heavy and hard to hold on a subject. A nice tripod and mount can help make your experience much more pleasant.
As an aside I began my astronomy with a pitiful refractor, with poor eyepieces on a rickety mount. Very frustrating. A 10" dob with one or two nice 2" eyepieces is a great way to see the sky and wont cost and arm and a leg. Think about 'goto' scopes or photo capable systems later....imho

 

[Damien Evans]

I'm thinking I'd like to buy a telescope, and learn to use it. I'd love to be able to check out the planets. I've had limited experiences with telescopes, but each time I was blown away by the experience.

Any suggestions of a telescope in the $300 range?

What's the least you (yes you) would spend on a telescope that you consider worth buying?

In that range the best I've found (in terms of aperture, build quality and ease of use) is the type I eventually got, a 6 inch (150 mm) Dobsonian Reflector. Cost me $330 Aud. Mine is a Saxon but there's a few other good brands making Dob 6's in the $270 to $350 price range, and it's a very easy scope to learn how to use. I highly recommend one.

Mine:
http://www.astronomyalive.com.au/re...-dob-6-152mm-reflecting-telescope-system.html

Some from kookbreakers store:
http://www.spectrum-scientifics.com/cgi-bin/commerce.cgi?preadd=action&key=1
http://www.spectrum-scientifics.com/cgi-bin/commerce.cgi?preadd=action&key=1765
http://www.spectrum-scientifics.com/cgi-bin/commerce.cgi?preadd=action&key=2

I also recommend you grab a copy of Starry Night, but at $150 for the pro version it isn't cheap.
http://www.spectrum-scientifics.com/cgi-bin/commerce.cgi?preadd=action&key=106

 

[jasonpatterson]

I'm thinking I'd like to buy a telescope, and learn to use it. I'd love to be able to check out the planets. I've had limited experiences with telescopes, but each time I was blown away by the experience.

Any suggestions of a telescope in the $300 range?

What's the least you (yes you) would spend on a telescope that you consider worth buying?

The best scope is the one you use. Lots of people have suggested particular models to look through, but some very important things to consider are where you want to observe (backyard or miles away?) and your physical condition (are you sufficiently at ease carrying 40-60 pounds through a field at night that you'd be willing to do it regularly?). If you're not in good health, dragging an 8" telescope (which you could probably find, used, without too much trouble in your price range,) tripod, and counterweights (depends on the mount type) around in the dark can be a real challenge, potentially enough to make you quit. Also consider whether your car/truck/whatever is big enough to move your gear and any passengers all at once.

Also important are the eyepieces you get with the telescope. You can purchase some that will be far too strong for either the instrument you'll likely be buying or for realistic use. Most of your viewing will be done at lower magnification than you'd think, and very high magnification is possible, but it very quickly comes up against the limits of resolution of the telescope. As a rule of thumb, the telescope will be unable to provide good magnification beyond 50 times its objective diameter in inches. That means that even in very good skies a 4" telescope is unlikely to be able to do any better than 200x magnification. You're also going to get a focal length when you're looking at the scope. To determine the smallest focal length eyepiece you could possibly use with your new telescope, you'd take the focal length of the scope and divide by the maximum useful magnification.

For an example, check out this one (Note, I'm not recommending this telescope as I've never used it, it's just an example. I do have an Orion scope though, and it's done well by me for the price.) It's got a 4.5" objective and 910mm focal length. With good skies you'd be happy to get 225x magnification out of it. 910mm/225 is about 4mm as the smallest eyepiece from which you could get a useful image. If you look, they're selling it with a 25mm and a 10mm, and in this case, a Barlow lens that doubles the magnification. Odds are very good that you'd not go beyond the 10mm usually, in all honesty. Basically, don't get too crazy buying high powered eyepieces, or a used telescope that comes with high powered eyepieces, as they are unlikely to be of much use in the long run.

Useful thread. It came at the precise moment my brother is becoming increasingly interested in astro observation and photography, and needs advice on a telescope.

I'd very very strongly recommend to both thatguywhojuggles and your brother that he try to find an astronomy club in his area (most have them) and do exactly what you suggest, try out a bunch of scopes side by side. Most clubs are full of people who are completely geeked out over their telescopes and the vast majority are more than happy to let you have a peek through theirs.

 

[DrBaltar]

I went to a star party to see Mars when it was closer than it has been in 60000+ years (back in August 2003, not any of the augusts since then that recirculated emails go on about). I really wanted a telescope and I kept kicking myself for not having one whenever some event like this would happen. I met some people there that talked to me about building my own, and made it sound doable. I bought the book "Build Your Own Telescope", which was very good for describing how to build several types of telescopes. I built a 6" dobsonian telescope, and even grinded my own mirror, all for around $300 in materials. I did send the mirror out to get a silver coating on it though. The mirror is accurate to 1/12 the wavelength of yellow light. Telescopes you buy at the store are only accurate to 1/4 wavelength.

It served exactly the purpose I originally wanted it for. If something occurs in the sky I can set it up and look at it. I have been able to see the shadow that Io casts on Jupiter. I have seen a 13th magnitude comet in the dark west texas skies. The moon and planets look great in it, and I have even seen a very detailed space station through it. I also mounted a green laser to help aim at objects. My only wish for it is that it could track the stars for long duration photography. But for everything else, it's great.

 

[BenBurch]

Don't be to sure about that.

I've been pretty miserable since they added five street lights to my street and two to my alley and the the new car dealers a mile away started lighting up their lots like the noonday sun all night long.

 

[CurtC]

I have even seen a very detailed space station through it.

Really? How did you track that?

 

[kookbreaker]

I've been pretty miserable since they added five street lights to my street and two to my alley and the the new car dealers a mile away started lighting up their lots like the noonday sun all night long.

There's a lot to be said for a simple hood for blocking the local lights and a light pollution filter for the stuff that makes the sky glow grey.