Refractor Telescopes

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What Are Refractor Telescopes?

The Ins and Outs of Refractor Telescopes

In simple terms, a refractor telescope uses a glass lense at its end to gather light, and as it travels through the telescope, the light bends. The light then bounces off a small mirror into the eyepiece, where the viewer sees a larger, sharper image of the object they're looking at. Another name for this type of scope is a "dioptric telescope".

"Refracting" literally means to bend and the first models of telescope were refractors. Galileo and others who designed the original technology found this method to be the easiest to make. Scopes used on rifles and other guns are refractors, as well as the small telescopes you find at general department stores. This type of scope tends to be tiny, but it's perfect for looking at the moon and planets within this solar system.

The benefits of choosing a refractor over any other type of scope start with the placement of the lense. It's sealed off, so you don't have to worry about cleaning it often, if ever. Also, images seen through the telescope are sharper and steadier thanks to the tube being immune to changing temperatures and climates.

There are very few large-scale refractors used for research because of the disadvantages these scopes carry with them. Few and far between, these drawbacks are the reason that most refractors are for commercial use and small observatories. The largest refractor telescope is at Yerkes Observatory, and measures in at 102 cm.

Chromatic abberation is one of the most common downfalls; light wavelengths bend differently, and because of this, you may see a rainbow effect around the object you're viewing through the lense. Refracting lenses don't allow ultraviolet light through them at all, and the thickness of the lense determines the clarity of the other lights that pass through. Also, the glass lense itself will eventually dip thanks to its own weight because it can only be supported by its ends.

Prices on these scopes vary, but considering the difficulties they present for makers of large scopes, the versions available to the public tend to be within a reasonable price range. For those looking to set up a scope in their backyard for clear nights, roughly $200-400 will get you a great quality starter scope. If you have more to spend, you can look into computerized telescopes, ones with tracking devices, larger lenses, or higher magnification rates. The prices depend on the maker and the technology.

The beginner lenses generally measure 60mm, 80mm, 90mm, and offer very clear pictures regardless of their small size. Telescopes come with a tripod to set them on, usually with a rotating ball at the center for easy navigation. You can buy a finderscope, which is essentially a miniature telescope that sits on top of the main scope and helps you focus in on the object you're viewing. It makes observing objects at a distance much easier, and much more accurate.

Overall, if you're looking to view the moon's surface or planets when they are within range, a refractor telescope is a perfect purchase for you as a beginner.


Refractor Telescopes 2012