![]() ![]() Following are some of the main Pros and Cons to consider for a refractor telescope. As power or magnification increases, contrast and sharpness decrease, thus the higher starting point for these that the refractor telescope offers makes it more suited for viewing the moon and planets with medium and high magnification. As a rule the nature of objective lenses provide for better contrast and sharpness which makes them ideal for higher power observations of bright objects like the planets. Refractors are also generally preferred for planetary observations. Thus the apo is the preferred instrument for astrophotography. The third and most expensive class is the apochromatic refractor, or apo for short, which generally uses a three element objective lens which virtually eliminates all chromatic aberration resulting in pinpoint stars with no color fringes. ![]() The next expensive class is the ED refractor which generally uses a two element objective lens, with at least one element made from extra-low dispersion glass, which corrects for almost all of the chromatic aberration. The cheapest is the achromatic refractor which uses a single element objective lens which suffers from chromatic aberration, or false color, the inability to bring all the frequencies of light to a focus, thus resulting in colored fringes or circles around bright stars and other bright objects like the moon and some planets. Refractors fall into three major categories: achromatic, ED ( extra-low dispersion), and apochromatic. The refractor telescope, as seen in the diagram above, uses a lens at the front of the telescope to collect the incoming light and direct it to the opposite end of the telescope tube where the light from the image can be focused and magnified. I hope this helps in deciding which first telescope might be right for you. Telescope Mounts will be discussed as a separate subject. Also, as a side note, you will notice that on this page I am only referring to Optical Tube Assemblies (OTA). So below is my attempt to try and simplify the basic differences, the pros and the cons, between refractor and reflector telescopes. Prices range anywhere from budget to I need a second mortgage, and everything in-between. Of course, the price ranges are just as varied as the telescopes themselves. The refractor telescope, which is what most people envision when they think of a telescope, and the reflector telescope, which is usually the more economical of the two. Although telescope types run the gambit from reflector to refractor, in addition to Schmidt-Cassegrain's and Maksutov-Cassegrain's, for the purpose of simplicity, on this website we will be focusing on the most popular telescope types that are usually a backyard astronomer's first choice. The bad thing is, there is a wide verity of telescopes available today, and that often adds to the confusion when someone new to the hobby is trying to navigate the new & used telescope market. The good thing is, there is a wide verity of telescopes available today. Either way, the varied technology for both scope types will certainly provide options to fit your budget.One of the first questions that confront the beginning backyard astronomer is which telescope they should buy. Of course, if you are equally drawn to both needs, you may just have to break down and get one of each. ![]() If your list includes wildlife viewing, outdoor adventures, or sports, and you know you’ll need the ability to pack up and go, the spotting scope is your best bet. If you find that most of your time will be spent on long-distance viewing and portability isn’t much of an issue, go for the telescope. Make a list of the ways you intend to use your new scope. One aspect to consider is that a telescope can be more of a home fixture, and the investment can last you for many years. Lens sizes, mounting, and electronic capabilities will affect your cost here, and refractors tend to run lower than reflectors. You could easily spend less than $300 and over $3000 on a decent telescope. Keep in mind that you’re also paying for something that’s both adjustable and durable. Waterproofing, weatherproofing, and lens power will certainly impact your cost, as well as the inclusion of a tripod. A good spotting scope can set you back anywhere from $80 to $1000 (and beyond). ![]()
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