A refractor generally will give sharp, high contrast views of the moon, planets, double stars and some star clusters. It offers excellent views of the moon, Jupiter and its moons, Saturn and its rings as well as dozens of other celestial objects.
It is a great daytime telescope also and a favorite for the cabin at the lake, at the ocean for ships and whale watching or for anyone with an open view to wildlife and birds. The advantage of a reflector, also called a Newtonian, is in the ability to build a larger mirror at a lower price than the lens of a refractor. All of the large telescopes in Hawaii, Chile and even the Hubble are reflectors, using mirrors up to 10 meters in diameter to collect light from distant galaxies.
For regular consumers, we rarely see a refractor with lenses larger than six inches in diameter. Lenses larger than 6 inches become too costly to manufacture and they introduce distortion that is difficult to overcome. So which should you buy? If your interest is in viewing the planets and the moon, some double stars, a few nebulas and a few star clusters, a refractor with a mm to mm objective lens may be a good choice.
Refractors with smaller lens from 60 mm to mm may also offer excellent views if the telescope has good quality optics, mount and tripod. You should be aware that these scopes of this size are often the ones promising far more than they are capable of delivering. Because the size of the mirror will determine how much light you collect, I always encourage people to purchase the largest reflector that they can handle and afford. Those who purchase telescopes with an eight or ten inch mirror are able to find more and more celestial objects.
Their interest in astronomy often grows more quickly than those with smaller telescopes because there seems to always be more and more to find and view. A reflector still offers excellent views of the moon and planets although a smaller refractor may offer a sharper, higher contrast view. These telescopes can be a bit more expensive due to additional manufacturing but they offer a compact telescope with a longer focal length and thus, higher power.
For many people the higher power is a disadvantage as objects are more difficult to find and appear to jiggle more readily because of the higher power. But on a stable mount and with a little patience you will enjoy the high magnification views from these scopes. Their advantage is sharpness, compactness, transportability and quick set-up. Different Views If you were to look directly through a refractor, the image would be upside down and reversed mirror image.
A 45 or 90 degree diagonal is almost always included with a refractor for ease of viewing and the diagonal also brings the image right side up. Sometimes the view is still a mirrored view with everything right-side-up but reversed. Views through a reflector are almost always inverted.
When looking at planets, star clusters and most celestial objects, the observer is not aware that the view is inverted. This makes most reflectors unsuitable for daytime viewing. Different Mounts 1. Dobsonian mount — Named after John Dobson who developed the initial simple design, this type of mount allows you to manually move a reflector simply and easily in all directions. If you can handle a 10 inch Dobsonian you will have even bigger and brighter views.
Many of us began our exciting journey of celestial discoveries with a Dobsonian. As recently as John Dobson, now 92 years old, was speaking to star parties and assisting with his astronomy group in San Francisco.
Equatorial Mount — Both reflectors and refractors come on equatorial mounts. With an equatorial mount you point the polar axis toward Polaris, the North Star. Once you locate the celestial object you will turn a single knob to keep the object cente red in the eyepiece in contrast to nudging along the Dobsonian. On some equatorial mounts motors drive the mount rather than having the observer turn a knob. While an equatorial mount may initially seem daunting and difficult, it can be quickly mastered and offers other advantages such as having the telescope up on an adjustable height tripod.
Alt-Azimuth Mount - This type of mount may be thought of somewhat like a camera tripod mount where you move it up and down and sideways. This is a mount that offers simplicity of use along with the advantage of having the telescope up on a tripod.
You find refractors and compound scopes on this type of mount. GoTo Mount — In recent years computerization has entered the field of astronomical equipment. Many young people come to astronomy through their technical knowledge which is applied to astronomy. A GoTo telescope usually needs some form of alignment with certain stars or planets and then is able to follow those objects and move its motorized mount to hundreds of other designated celestial objects.
Celestron and Sky-Watcher are two manufacturers of GoTo scopes that are popularly available. What Will I See? We have chosen a fairly arbitrary standard for recommending a telescope. Many people have traced the beginning of a wonderful journey in astronomy to their first view of Saturn and its rings. Unless otherwise noted, all of the telescopes we recommend will allow you to see Saturn and its rings, Jupiter and its four moons, the Orion nebula, hundreds of craters on the moon, and numerous star clusters and double stars.
All telescopes will allow you to see the oval structure of the Andromeda galaxy. Our Recommendations: The best value in an astronomical telescope is the Dobsonian reflector. You will need some simple sky charts such as those available in the monthly astronomy magazines or in NightWatch to know where to point the telescope.
I am not aware of anyone who has returned a Dobsonian because it disappointed them. Again, we recommend the largest scope that you can manage and afford. This scope is easily transported if you have space in your vehicle for it. You will also need a place to store a Dobsonian.
While Dobsonians can be purchased in many larger sizes, the most popular sizes are with 6 inch, 8 inch and 10 inch mirrors. The 8 inch and larger Dobsonians now come in "collapsible" styles which make them easier to transport and store. Another economical reflector is the 5 or 6 inch telescope on an modified Dobsonian mount.
Because of the higher magnifications provided by these telescopes, the object being observed will more quickly move out of view, and so they are often purchased with electronic tracking mounts to follow the targets as they move.
The right telescope for you can be determined by deciding where and how you will use your telescope; maybe at home, or perhaps to take to dark-sky sites. All three designs are available as basic models or with fully computerised controls and even built-in wi-fi for operation via smartphone. Whatever your choice, refractor, reflector, Cassegrain, it is advisable to make your purchase from specialist astronomy dealers that know all about the telescopes they offer and can answer the inevitable questions.
There is a wide variety of telescope available on the market, and it pays to do research before buying. Our guide below provides a look at three different types at either end of the price spectrum. The LT 70AZ boasts a 70mm diameter front objective lens, fully coated optics and a focal length of mm.
It comes as a sturdy yet lightweight aluminium tube mounted on an altaz fork mount and features slow-motion control.
The refractor comes with two eyepieces — 25mm and 10mm — plus a Barlow lens and erect image star diagonal. One nifty inclusion is the StarSense Explorer phone dock, which can be used to fit a smartphone and turns this manual telescope into a hi-tech gadget that can locate celestial objects using your phone and the StarSense app.
At six inches in diameter the Evostar ED DS-Pro is probably the maximum manageable size refractor for most amateur astronomers. Also, we found that planetary nebulae M57 and M27 contrasted the background sky very well indeed. We took a look at globular clusters and open clusters and found these sharp and clear: so too lunar views and in particular crater walls. Where to buy: High Point Scientific. The whole setup is easy to assemble and operate and certainly provides a welcoming introduction to observing the night sky.
The Newtonian design uses a parabolic primary mirror to collect and focus light from your celestial target, while a flat secondary mirror reflects it to the eyepiece. The ExplorerPS is equipped with a fixed mirror cell for the primary mirror, which many will be pleased to hear comes pre-collimated, meaning it should only need adjustment every now and then with the supplied Allen key.
An accessory tray for eyepieces also makes for a good as a tripod-leg tensioner to help stabilise the setup. The VX8 is affordable system, and with the rolled aluminium tube weighing 7kg and measuring just 86cm long, many will find this easy to transport and lift onto a mount using the tube rings and dovetail bar.
Read our full Orion Optics VX8 review. Where to buy: Orion Optics. An altaz Dobsonian telescope makes for a great beginner telescope, as simplicity is the name of the game. The telescope tube comes with tube rings attached, but the rocker base on which it sits is a flat-pack and requires a bit of assembly.
Indeed, one of the great things about this scope is that you can set it up and get observing within minutes. This also helps take advantage of breaks in the clouds. Read our full Bresser Messier 8-inch Dobsonian review. Where to buy: Bresser. This is helped by the light rocker box, which most people would find easy to move into an observing spot. A 32mm super wide angle eyepiece, mirror-cooling fan, battery box and a red dot finder complete the system.
We observed Jupiter and found the planet snapped into focus and we could see belt and spot features. We also observed the Ring Nebula and found all of these targets looked amazing.
Where to buy: Omegon. Maksutov-Cassegrain telescopes use mirrors and a front corrector lens to make for a compact, relatively portable optical tube. Orion is committed to helping you enjoy high-quality astronomy equipment at affordable prices. Make the best choices by taking a few moments to review the vital information in our online Buying Guides. See the eCatalog. Please send me email about sales, new products, and astronomy.
By signing up for email, you agree that Orion has the right to use your data for such purpose. Now an employee-owned company, we pride ourselves on an unswerving commitment to best quality products, value and unmatched customer care. Orion offers telescopes for every level: Beginner , Intermediate , and Advanced. From our entry-level beginner telescopes for amateur astronomers to our Dobsonian telescopes to our most advanced Cassegrain telescopes and accessories , you can find the best telescope for you.
Because we sell direct, we can offer you tremendous value at a great price. Not sure how to choose a telescope? Orion's Telescope Buyer's Guide is a great place to start. Orion binoculars are known for quality optics at a great price. We offer binoculars for every viewing interest, including astronomical binoculars , compact binoculars , waterproof binoculars , birding binoculars , and sport and hunting binoculars.
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