How to choose a telescope for astronomy

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Now that you have finally decided to take the plunge and treat yourself to a telescope that you have always wanted, how do you make up your mind about which type is best for you?

Well, at Earthandwind we believe in giving our customers the full picture as regards information about the items we offer for sale on eBay, so here is a quick'n'easy guide to help you choose the right telescope!

Types of telescope

Refractor

An optical system that utilizes a series of glass lenses to refract or bend the light from a distant object such that it can be focused to a point and magnified by an eyepiece. Popularized by Galileo in the 17th Century. It is sometimes reffered to as a Galilean refractor.

Reflector

The optical system in a reflector uses a primary mirror to reflect the light from a distant object such that it can be focused to a point and magnified by an eyepiece. Popularized by Sir Isaac Newton in the 17th Century, it is sometimes referred to as a Newtonian reflector.

When selecting a telescope, consider which target objects you plan to explore as well as your level of experience. For viewing most night sky objects, you'll want a telescope with as much aperture as possible. Keep in mind that as the size of the objective lens or mirror increases, so does the size of the telescope. So be sure to select a telescope that isn't too heavy to manage or too complicated for you to set up - especially if portability is a necessity.

Refractors

Refractors are less affected by atmospheric instabilities making them perfect for observing the Moon and planets. Perfect for first time and novice astronomers, small refractors are lightweight, portable and require very little maintenance. And, if you're interested in viewing both land and celestial objects, refractors are equipped for both uses.

Reflectors

Reflectors feature larger apertures for a wide range of viewing at an affordable price. Designed with the eyepiece located at the top of the tube, reflectors are more comfortable to use for viewing night-sky objects such as nebulas, the Moon, planets and galaxies. Reflectors tend to be heavier and larger than refractors.

Magnifying power

Forget about magnification! It is a myth that high magnification equals good views. Looking through a telescope at high power requires a rock-steady (expensive) mount, and things are very difficult to find through a telescope at high power. Imagine trying to look up at the sky through a drinking straw and trying to find one particular star, it's near impossible without a lot of experience or a computer controlled telescope. You also need an exceedingly steady atmosphere to see any real detail at high magnifications. Further, many of the coolest objects, like galaxies and nebulae, can only be seen fully under low power because of their size.

As an example, a 25x magnification provides a field of view that is perfect for the Orion nebula. Sometimes I'll go to 50x to see a planet, but then the atmosphere starts boiling in the eyepiece and the view is not very good. Not to mention that a gnat farting 10 feet away will cause the scope to shake violently!

Taking photos through your telescope

Imaging is hard, time-consuming, expensive and frustrating. The first thing people seem to want to do with their new telescope is take pictures through it. While I completely understand this desire, it's important to realize the this is a very hard thing to do. Even experienced professionals are frustrated by their imaging efforts. Imaging through your telescope means that you're spending all night tweaking focus knobs, dealing with laptops and software, setting exposure times, taking calibration images, guiding the telescope, and a whole slew of other things. Imaging is all about the equipment, observing is all about the sky. Before you start trying your hand at imaging, you need to develop basic telescope and observing experience. If you don't take the time to learn the sky and how to observe, I promise you that all the money you spend on imaging equipment with be wasted. Take your time, the universe will still be there when you're ready.

Eyepieces

Lower power eyepieces provide a wider field-of-view and a brighter image making them ideal for viewing the full Moon and planets, star clusters, nebulae and the constellations. To focus in on the finer details of the Moon and planets such as mountains, ridges and craters, use an eyepeice with higher magnification.

Mounts

There are two basic types of telescope mounts, the altitude-azimuth (or atlaz) and the equatorial.

The mount secures the telescope to the tripod. It allows you to move your telescope horizontally and vertically. There are two primary types of telescope mounts, altitude-azimuth (or altaz) and equitorial. Atlaz mounts move u-down and left-right. Equitorial mounts are tilted to align with the rotational (polar) axis of the Earth.

Easy Track Mount

An altaz mount that allows quicker and easier set-up and storage and reduces image shake caused by wind or ground tremors.

Equatorial Mount

An advanced telescope mount that compensates for the earth's rotation.

What can my telescope show me?

You are not going to see anything remotely like what you see on the NASA websites or on calendars and posters. Those images were taken by multi-million dollar spacecraft that were processed by a team of scientists whose job is to modify them into pretty pictures. With the exception of the planets and the Orion Nebula, for most galaxies you're going to see a smudge of light through even the largest amateur telescopes.

That's why any professional astronomer worth his salt will tell you -- if you've never used a scope before, concentrate on the planets. They are exquisitely beautiful and never fail to please. You can see the bands of Jupiter as well as its moons. I love it when Saturn is up during a star party. I love being the man who shows someone Saturn through a telescope for the first time, their reactions are always the same: "WOW! LOOK AT THAT! MAN, THAT'S AWESOME! OH MAN THAT'S COOL!" and then they get real quiet for about 5 minutes while they just stare into the eyepiece. It's usually that person who hangs around me for the entire night asking all kinds of questions and begging me to show them more stuff. The planets are breathtaking through even the smallest telescopes and binoculars.

There you go!

If you come away with anything from reading this, I hope it is that, when starting out in amateur astronomy, simple is best. The night sky has a serene, simple beauty that doesn't require a lot of gizmos to enjoy. The telescopes I use the most are the ones I can just grab and set up in minutes. I have to really plan out my observing nights with my larger scopes or for an imaging session, and if it's really cold outside, sometimes I just forget it.

And remember -- if you're outside looking at the stars without a big smile on your face or a feeling of awe in your heart, you're not doing it right!!

Now please go to our eBay shop Earthandwind to look at our telescopes on offer just for you!

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