Joy Davenport offers the following royalty-free article for you to publish online or in print. Feel free to use this article in your newsletter, website, ezine, blog, or forum. ----------- PUBLICATION GUIDELINES - You have permission to publish this article for free providing the "About the Author" box is included in its entirety. - Do not post/reprint this article in any site or publication that contains hate, violence, porn, warez, or supports illegal activity. - Do not use this article in violation of the US CAN-SPAM Act. If sent by email, this article must be delivered to opt-in subscribers only. - If you publish this article in a format that supports linking, please ensure that all URLs and email addresses are active links. - Please send a copy of the publication, or an email indicating the URL to [email protected] - Article Marketer (www.ArticleMarketer.com) has distributed this article on behalf of the author. Article Marketer does not own this article, please respect the author's copyright and publication guidelines. If you do not agree to these terms, please do not use this article. ----------- Article Title: Buying A Telescope - What You Need To Know Author: Joy Davenport Category: Science, Electronics Word Count: 436 Keywords: telescope parts,Bushnell Telescopes,reflecting telescope,telescopes for sale,telescopes for kids, Author's Email Address: [email protected] Article Source: http://www.articlemarketer.com ------------------ ARTICLE START ------------------
Giving a telescope as a gift - whether to a child or to yourself - is a chance to open up new vistas of curiosity and new horizons of exploration. Finding telescopes for sale can sometimes be tricky, particularly if you're just getting into the hobby. There are three basic families of telescope optics in consumer grade telescopes; most of the telescopes you find for sale will be in one of them. The three families are refractors, reflectors and catadioptic telescopes. All of these are made of different telescope parts and they have different properties to work with. Refractors dominate the low end of telescope production; they're also the basic mechanism behind field glasses and binoculars. The classic "two lens" telescope is a refractor, and provided the lenses are small, this makes for inexpensive telescopes. Most of the very cheap telescopes for sale have plastic lenses; while these can be serviceable, the result of plastic lenses and cheap construction methods results in something that's good for being a celestial tourist, but not serious observational astronomy. Refractors have narrow fields of view, and they are limited in their focal lengths by the basic rules of optics - refractors longer than about 3 feet are unwieldy. Most refractors will present the image inverted, due to the optical process, and a useful telescope part to have is an image rectifier. Low quality refractors are also prone to chromatic aberration, which distorts the colors of whatever you're looking at through them. At the mid range of telescopes are reflectors; these are also called Newtonian reflectors, and have a concave mirror that focuses the light into a guide mirror that puts the image out on a viewport on the side. Newtonian reflectors are good basic telescopes, and unlike refractors, can come in wide angle lenses. Unlike refractors, they do not have chromatic aberrations, but they do flip images from left to right, rather that upside down. They can run into problems with humidity (fogging of the optics), and can be tailored to nearly any range of astronomical uses. At the upper range of telescopes for sale are Schmidt-Cassegrain reflectors, also known as catadioptic telescopes; these combine a number of the ease use features of Newtonian reflectors with the enclosed mountings of refractors; these telescopes tend to be in the thousand dollar and more range, so likely aren't suitable for beginners. Important telescope parts include image inverters, Barlowe lens extenders (which increase the magnification of an existing eyepiece) and eyepieces. It's the eyepieces and the focusing mechanism on the telescope that are some of its most important parts; fortunately, they're in fairly standardized sizes and ranges. Take a look at this site for your One-Stop-Source of Best Selling Telescopes and Telescope Parts, and find helpful tips in buying a telescope by going here: http://www.telescopepartsplace.com. ------------------ ARTICLE END ------------------ [Non-text portions of this message have been removed]
