Not just because they are a good general-purpose telescope, which can be used for viewing both deep sky and solar system objects, but because an entry-level reflector (with a mirror 6-8 inches in diameter) can be bought for a very reasonable sum. Almost 350 years later, reflectors are probably the most popular type of telescope. It is generally accepted that the first working reflector was built by Sir Isaac Newton back in 1668, although others had designed similar instruments before him. Light from the night sky enters the tube, hits the mirror, reflects off it back up and is diverted out of the tube’s side by a smaller, secondary mirror into a focusing eyepiece. They are basically a tube, open at the front, with a large mirror mounted down the bottom end. (Image credit: Orion)Īs their name suggests, reflector telescopes use mirrors instead of lenses. The Orion StarBlast II 4.5 EQ telescope, an example of a reflector telescope. However, more advanced refractors, just like large reflectors, take a lot of setting up and aligning before they can be used. Unlike a reflector, refractors don’t need aligning or collimating before every use. How easy are refractor telescopes to use?Įntry-level refractors are easy to assemble and maintain. The telescope then finds that object in the sky for you, slewing around until the object is centered in its eyepiece. After aligning the telescope on the Pole Star, and then on several additional “guide stars,” you enter the date and your location into the computer using a keypad on a handset, then select an object from the telescope’s own database by scrolling through various menus. Many modern refractors are mounted on computerized “GoTo'' mounts, which make them very easy to use. More complicated mounts allow you to find objects in the sky by first aligning the telescope with the Pole Star and then turning dials on the mount until the telescope is pointed at a specific set of coordinates in the sky. Refractors on simple alt-azimuth mounts are essentially “point and look'' telescopes - you just move the tube up and down and from side to side until it’s pointed roughly toward what you want to look at, then align the telescope more accurately using a small “finder scope” mounted on the main tube. However, a budget refractor’s poor tripod can often be replaced with a good photographic tripod and the refractor tube mounted on that. Small “tabletop” tripods are particularly useless, and telescopes that come with those are a little better than toys, to be honest. Many of the “budget” refractors available are actually of quite good quality optically, but are let down by the poor quality tripods they come supplied with. As with any telescope, it’s important to pick a refractor mounted on a stable, steady tripod or the image you see looking through it will jump around so much it will be useless. Modern refractors come on a wide variety of mounts, but it should be noted that all refractors are supported by tripods. Computerized go-to mounts can do the hard work for you.Alt-azimuth mounts can make aligning to a target easier.Not great for viewing galaxies and nebulas.The main disadvantages of a refractor telescope are: ![]()
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