We’ve rounded up the best telescopes for stargazing in this comprehensive guide. As well as picking the very best models, we’ve included telescopes to suit every level of astronomer and catered for every budget.
At the bottom of the guide, we’ve described what type of telescopes are most suited to which activity (e.g., Lunar or deep space observations). This may help you decide what is best for you out of the models we’ve selected to be on this list.
If you’re an avid bargain hunter, check out our telescope deals page, which is regularly updated with the best telescope deals as we find them. Deals aside, though, if you’re seriously interested in getting the best stargazing experience, this is the guide for you as we’ve listed the best models from top manufacturers, available now at reputable retailers.
Best telescope deal March 2023
Aside from this comprehensive list, we do also have brand-specific telescope guides for Celestron, Skywatcher, Meade, and Orion deals for those loyal to their favorite brands. Like this guide, we also keep those updated year-round, so they’re always worth checking out.
We also have selected our favorite budget telescopes under $500, best beginner telescopes and best telescopes for kids incase you’re looking for those specifically.
Aside from telescopes, the best binoculars can be useful skywatching devices, too and the best cameras or best cameras for astrophotography will help you capture wonderful night sky images if night sky photography is an avenue you want to consider.
While you’re here though, we’ve listed the best telescopes overall for beginner, enthusiast and professional observing respectively.
Best telescopes 2023
Why you can trust Space
Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you. Find out more about how we test.
An excellent telescope for the beginner or those on a tighter budget, the Celestron Inspire 100AZ is a great choice for those looking for a complete package that offers more in the way of accessories than most starter telescope bundles.
The Inspire 100AZ comes with a 90-degree erect image diagonal with a 1.25-inch fitting that makes the telescope suitable for terrestrial (daytime/on land) and celestial views, a pair of eyepieces (20 mm and 10 mm), a red LED flashlight for preserving vision, an accessory tray, StarPointer Pro finderscope and a smartphone adapter for basic astrophotography. Be mindful that given the refractor’s focal ratio, the Inspire 100AZ is limited to short-exposure photography.
During the observations we made in our Celestron Inspire 100AZ review, we noticed a small amount of false color (purple color fringing), and a slight blurring in the field of view was noticeable. The latter is easily resolved with a careful selection of eyepieces, so we recommend investing in additional eyepieces to make the most of the Inspire 100AZ’s optical system and to ensure that it translates into the quality of your photos, if you’re taking them False color, on the other hand, is to be expected in telescopes at this price point but it doesn’t ruin the experience unless you’re exceptionally particular about color accuracy.
The overall build of this refractor is impressive. The StarPointer is a pleasant surprise since it’s able to pick out faint stars under moderate light pollution for an accurate star-hopping experience.
After undertaking our Celestron Astro Fi 102 telescope review we’d say this is perfect for beginners who don’t have prior knowledge of the night sky but want to start learning and enjoying it straight out of the box.
It’s not a budget scope by any means, but if you’re looking for a telescope that comes from a trusted brand that is highly portable, this one is worth your consideration.
This is a good grab-and-go option when weighing in at just 6lbs (2.7kg). It doesn’t have a huge footprint as some telescopes do, so you can leave it set up at home without compromising your space too much, though it is easy enough to pack away and reassemble at will.
We think the final finish on the telescope looks and feels a little toyish, and compromises such as the materials used have been made to keep the scope as lightweight as possible. Despite the slightly lackluster final finish though, the image is attractive, and you can explore the detail on the Moon’s surface, Saturn and its rings, Mars and Jupiter. You may also see nebulae and other deep sky objects in the right sky conditions.
It’s very quick and easy to sync with Celestron’s SkyPortal app, which contains approximately 100k celestial objects to explore.
Boasting the build quality we’ve come to expect from the other models in Celestron’s NexStar range, the 4SE is optically comparable with the aforementioned Celestron Astro-Fi 102 but instead of relying on a smartphone, this model comes with a chunky and tactile hand controller. It is a good buy for beginner astronomers as it’s very simple to use and produces a clear and bright picture which is why we gave it four out of five stars during our Celestron NexStar 4SE telescope review.
The field of view is somewhat limited, which some users may find frustrating when manually slewing, but as Celestron’s SkyAlign software and GoTo system finds objects for you, this isn’t a deal breaker. The hand controller also allows nine different slewing speeds allowing for small corrections or a quicker scan of the night sky if you choose.
Given the power-hungry nature of the NexStar SE scopes, an external power supply is advised. The scope can otherwise quickly drain a whole pack of AA batteries. This does further limit portability further unless you are using it in combination with a portable power station (opens in new tab).
(opens in new tab)
Celestron StarSense Explorer LT 114 can be enjoyed by beginner and intermediate skywatchers alike. It will be especially desirable to busy users who lack the time required for lengthy set-up procedures. During our Celestron StarSense Explorer LT114 review we timed assembling this telescope — it took less than 20 minutes!
Celestron’s StarSense technology is built into this reflector, which provides an extremely easy way to align the telescope. The skywatcher needs to download the StarSense app from Google or Apple (opens in new tab) and take a smartphone image through the eyepiece, the app then works out which stars are in the telescope’s field of view to calculate which way it is facing, clever.
The app not only provides an immersive experience but also offers interesting information on each of the targets you observe, giving you a better understanding of what you’re looking at.
You can enjoy the gas giant of Jupiter (opens in new tab) by using the 10 mm eyepiece. The views are clear, but you’ll need a selection of eyepieces (check out our best eyepiece buying guide) and filters in order to pick out the coloration of the atmospheric bands. The planet’s largest moons are visible as clear, sharp points of light. Views of the moon, Venus (opens in new tab) and the Beehive Cluster (Messier 44) are also pleasing and clear.
We found that the StarSense Explorer LT 114 is built sturdily and operates smoothly when slewing from one target to another. The scope needs to be manually operated, so you don’t get the ease of tracking that computerized telescopes would offer. However, some skywatchers prefer the hands-on versus electronic approach, and what’s more, the price is lower.
Of course, you get the usual high-quality optics that we’ve come to expect with Celestron telescopes and the aperture is a good size too. All in all, this is an excellent choice for a budget-friendly backyard telescope.
Best telescopes for enthusiasts
(opens in new tab)
The optical system of the Celestron NexStar Evolution 9.25 (opens in new tab) ranks as one of the best we’ve ever had the pleasure of observing the night sky through. With no interference or optical defects in the field of view, this high-quality instrument offers sights of a wide selection of astronomical targets with impressive clarity and contrast.
Although it is expensive (sitting around $2850), you get a lot of value for money with this telescope and its setup. The list of accessories you get include an attachable camera, a red dot finderscope, an international AC adapter, hand control for a seamless AutoAlign process and 13mm and 40mm eyepieces.
The stand-out piece of equipment with the NexStar Evolution 9.25 is undoubtedly its single-fork arm. Observers can slew from one target to the next and continue onwards at the touch of a button for up to 10 hours of continuous use, thanks to its rechargeable lithium-ion battery.
Built into the mount is the telescope’s very own Wi-Fi network, allowing the instrument to connect and control via the Celestron SkyPortal app (downloadable for free on iOS (opens in new tab) and Android). Being motorized, the mount can track objects as they move across the sky, making the NexStar Evolution 9.25 a must-try for astrophotography.
If you have the budget and if you’re looking for a complete high-definition tour of the universe, then we fully recommend this GoTo to seasoned skywatchers. The only downside is that the NexStar Evolution 9.25 is tricky to transport due to its weight, meaning that skywatchers will need to consider this before planning any trips beyond the backyard — a small trade-off given the telescope’s robust and high-quality design.
When we reviewed the Celestron Astro Fi 130 telescope we liked it a lot and think it’s excellent value for money. While it’s not necessarily a budget telescope, it is a lot more affordable than a few of the other telescopes in this guide, we think it’s excellent value for money.
If you’re new to stargazing, or even if you just don’t have a lot of experience, this telescope can give you an astronomy experience to marvel at using telescope technology and good optics, serving as a virtual guide to the night sky.
A 130mm aperture means that plenty of light is able to travel through the lens, making the night sky targets clearly visible and giving you amazing views of stars. A focal length of 650mm means you’ll get a wide field of view (you can see a lot at once).
This telescope is also sturdy but still lighter than some other scopes you might consider for the same experience, so it scores well on ease of transport. You also get a stable tripod, a red dot finder and eyepieces, which makes this even better value for money.
We can only think of two things that let you down a bit with this model: the battery life drains a little quicker than you might want, and the eyepieces aren’t the best. We think you should consider upgrading the eyepieces for a better experience, but for value for money, we highly recommend this scope.
Best Computerized or GoTo telescopes
The first of three of the NexStar telescopes on this list, and for a good reason. The Celestron NexStar 8SE is an excellent option for beginners and seasoned skywatchers. This telescope makes it easy for novices to view the night sky without knowing much about astronomy. At the same time, more experienced stargazers can use it to explore deeper into space or even attach a camera for impressive astrophotography.
If you pay a good chunk of money for a telescope, you can expect to receive exceptional optics with extraordinary views of a wide range of celestial objects.
The NexStar 8SE by Celestron is renowned and has earned the title ‘The World’s most beloved telescope.’ It is the number one bestseller on B&H Photo (opens in new tab). Featuring StarBright XLT optical coating, this telescope provides unparalleled clarity and contrast for viewing planets and the moon. Jupiter, its moons, Saturn, and its rings are breathtakingly vivid with no chromatic aberration or color fringing. Its 203.2 mm aperture lens allows for excellent views of deep-sky objects.
In our Celestron NexStar 8SE review, we walked you through what it’s like to get everything set up, and it’s very straightforward. No prior knowledge of the night sky is needed, as you can use Celestron’s SkyPortal app or any other stargazing app to help you find two stars for the alignment process.
Once the telescope is aligned, you can use the solid-in-the-hand, hand-held controller to direct it to any item in its massive database. This includes planets, galaxies, double stars, star clusters, and nebulae. A fantastic option for beginners and indecisive people is the ‘sky tour,’ which automatically directs the telescope to different interesting cosmic objects.
The motor runs smoothly, and the results are precise. Automatic tracking is a dream for astrophotographers, enabling them to take long exposures, which can then be stacked post-shoot to create beautiful images.
The Celestron NexStar 8SE comes with a hefty price tag, but it is well worth the investment for those serious about skywatching or astrophotography. Although it may be too pricey for those who are only casually interested in the solar system, it is an excellent choice for those who plan to engage in these activities for the long term.
(opens in new tab)
As an introduction to the world of GoTo skywatching, the Sky-Watcher Skymax 127 SynScan AZ (opens in new tab) is a must-have for observers on a tighter budget. The SynScan AZ hand controller offers information on over 40,000 astronomical objects, which includes the most complete catalogs (Messier, NGC, IC and SAO) of deep-sky and solar system targets.
The astronomer has everything they need for a successful night under the stars: good quality star diagonal, 2x Barlow with a camera adaptor, 6×30 finderscope, a stainless steel tripod and an accessory tray.
Assembling the instrument is easy and, given the weight of 39.7 lbs. (18 kg), the Sky-Watcher Skymax 127 SynScan AZ is light enough to carry across the backyard without a great deal of effort. Skywatchers have the choice of powering the Servo Drive with 8 AA batteries or a 12V power supply — because batteries tend to drain quickly in when it’s cold, we recommend investing in the latter for uninterrupted observations with the SynScan technology.
Alignment is simple, using two stars to set the instrument up, but beginners may need practice in getting this just right — we recommend becoming acquainted with the Skymax 127 before dark, ensuring that you read the manual from cover to cover.
In terms of optical prowess, we don’t have any complaints. We can fit a waxing gibbous moon phase in the field of view and, after tweaking the focuser, the craters and lunar mare come into exquisite focus, with lovely contrast and clarity. A moon filter offered even better sights. Slewing over to the star-forming region, the Orion Nebula (Messier 42), is also picked out easily with the 5-inch (127 mm) aperture — it appears as a dusty patch of light with the Trapezium Cluster’s member stars dazzling with brilliant clarity at the nebula’s heart.
The stainless steel tripod can be a bit unstable, so we suggest supporting the setup while slewing in windy conditions.
Celestron’s range of NexStar telescopes has a well-deserved reputation for excellent optics, user-friendly assembly and a plethora of features. The telescope exemplifies all of these which we outlined in our Celestron NexStar 6SE review.
If you’re looking for a telescope with great light-gathering capabilities and a vast selection of astronomical objects to explore, this is an excellent choice. The 5.91-inch (150 mm) aperture provides superior performance compared to the Meade StarNavigator NG 114, while the NexStar+ hand controller contains an expansive database with over 40,000 objects. Unfortunately, extra eyepieces will need to be purchased in order to get the most out of the telescope, and even then, not all objects listed in the database can be viewed in great detail.
The NextStar 6SE offers a great way to explore the night sky using its ‘tour mode’. It will guide you through different targets across the sky, or in specific constellations, so you can observe like never before. This is perfect for those who don’t know what to look for or just want to get straight to observing interesting celestial objects that have been chosen for them.
The SkyAlign technology is simple to use and gets you pointed in the right direction fast. The motorized mount also has nine slewing speeds on top of its different tracking rates. All of this sounds brilliant, and it is, but there is a downside. The NexStar 6SE’s battery can drain very quickly, so we recommend powering the setup with an external power source.
Astrophotographers may initially be displeased with its slow f/10 focal ratio, limiting the NexStar 6SE to being a planetary or lunar imager at best. Still, there is the facility for more advanced users to switch out the secondary mirror for their camera, increasing the focal ratio to an astrophotography-friendly f/2.
(opens in new tab)
The larger the aperture of your telescope, the more light it can drink in, allowing you to resolve the finer details in astronomical objects and see deeper into the universe. With a 12-inch (305 mm) objective lens, this collapsible Dobsonian from Sky-Watcher lives up to the nickname of ‘light bucket.’
The Dobsonian telescope offers a simple design. Its GoTo feature and motorized alt-azimuth mount, navigated with a SynScan hand controller, make it easier than ever to calibrate the telescope and get fantastic views of the night sky.
Over 40,000 targets are offered in the database and, we have to say that seeking out faint fuzzies was our first port of call with the Sky-Watcher Flextube 300 SynScan. The Andromeda Galaxy (Messier 31) is an incredible sight, with some dust lanes visible and the bulge glowing brightly. Its satellite galaxies are also visible as points of light in the field view.
This Dobsonian telescope has a focal ratio of f/4.9, making it suitable for photography. Those with the ability to do so can capture stunning images with this device, taking advantage of the abundance of photons it can gather.
The Sky-Watcher Flextube 300 SynScan is heavy, but its collapsible design allows it to be easily stored in the trunk of a car for when you need to go to dark-sky parks or star parties.
Despite its costly nature, the Sky-Watcher Flextube 300 SynScan is a must-have for any hobbyist, given its generous aperture, excellent imaging capabilities, and GoTo capability.
Best Smart telescopes
At $2499 (opens in new tab)/£1982, the Vaonis Vespera is the smallest and most reasonably priced smart telescope to date. This telescope from French startup Vaonis is a smaller, lighter version of its robotic older sister, the Stellina.
Named after the Latin word for ‘evening,’ Vespera does not have an eyepiece like traditional telescopes but instead captures and shares images of the night sky with up to five connected smartphones or tablets through a mobile app called Singularity (opens in new tab).
The Vespera is effectively a camera for taking stunning pictures of deep sky objects, even in light-polluted cities. It is not intended for observing the moon and planets, but it can be used to capture remarkable images of star clusters, nebulae, and galaxies. Here is all the information you need to know about how the Vespera works.
The Vespera is an impressive device that combines three technologies: star pattern recognition software, image live stacking technology, and an app. When switched on, its Sony IMX462 image sensor can detect a target in five minutes and take one photograph every 10 seconds (this varies depending on the target). This noise-canceling process can be seen in real-time on the Singularity app, resulting in a clearer, more contrasty and colorful image. We in our Vaonis Vespera review we found that the images were a little soft, but they could be enhanced with post-processing.
Additionally, it uses a planetarium to generate a ‘tonight’s best’ list of celestial targets and an algorithm to determine the camera settings for viewing each target.
The eVscope 2, a telescope designed with great finesse, is ideal for photographers who are new to astronomy and have a considerable amount of money (about $5000 (opens in new tab)) to spare or for astronomers who desire an all-in-one system that is effortless to set up and use. Even though it may not be greatly appreciated by experienced telescope users accustomed to a more traditional viewing method, it can still create remarkable images.
The Unistellar eVscope 2 is a step away from traditional telescope stargazing and instead hosts an in-built camera, sleek design and electronic eyepiece. It is the second iteration of the eVscope line and has some noticeable improvements in both design and accessibility. It features a 4.5-inch (114mm) reflector with a focal ratio of f/3.9, which makes it ideal for viewing celestial objects such as nebulae.
Inside is a 7.7MP image sensor and new to the eVscope 2 is an electronic eyepiece designed by Nikon for those that want to get tactile with the telescope. The simple layout, stylish design, and excellent smartphone app user interface makes the eVscope 2 a doddle to use and photograph the night sky with, especially with its enhanced tracking feature, which we were very impressed with in our Unistellar eVscope 2 review.
Due to the high cost of all the premium features, in reality, it is reserved for those with a substantial budget.
The Vaonis Stellina telescope is unlike any other model on the market. It doesn’t even look like a telescope, a fact that may put off traditionalists. Boasting a smart design, it does away with the need for finderscopes and eyepieces. Instead, it relies on a Sony CMOS sensor and a smartphone app to provide stunning views and take amazing color images of the night sky. This telescope is more expensive than the competition, but it does include a free download of the Stellina app with 100 targets.
While it isn’t ideal for studying planets, we discovered in our hands-on Vaonis Stellina review that it excels in producing images of bright deep-sky objects and the surface of the moon. It displays star clusters, nebulas, and galaxies in great clarity, with 6.4MP images at 3096 x 2080 resolution in JPEG and RAW format.
It is perfect for astrophotography or group viewing as up to 10 devices can be connected at once. It also comes with a light pollution filter which is helpful in areas that suffer from skyglow, and it can easily handle changes in weather.
Though pricey, we think the Vaonis Stellina is worth the cost due to its sophisticated technology, sturdy and stylish build and reliability.
Best telescopes to observe planets
Sitting at a price of less than $300, the Sky-Watcher Explorer 130 EQ2 is an excellent choice for those serious about taking the first steps into the world of astronomy.
Unlike other models at a similar price point, this telescope ships with an equatorial mount. When it is aligned with the Earth’s axis, it makes it simple (after some practice) to track objects in the sky once you’ve found them, as the Earth rotates.
It has a good-sized aperture at 5.1 inches, which means, unlike the models above, you will be able to explore deep sky objects, albeit only the brightest ones.
While not as long as the Celestron Inspire 100AZ, the Sky-Watcher Explorer 130 EQ2’s long tube length results in f/7 and makes high magnification possible. During our review of the Sky-Watcher Explorer 130 EQ2, using the supplied Barlow lens, we could easily get sharp views of the Jovian System (Jupiter, its rings and moons) and Saturn’s rings looked impressive.
This telescope is best suited for backyard stargazing, mainly due to its 12.6kg combined weight, which makes it a little more of an ordeal to take it out and about on sky-watching trips.
The Orion Skyline 6″ (opens in new tab) telescope is a great choice for beginner and intermediate astronomers alike due to its easy-to-use nature and high-quality optics.
This telescope offers an impressive 152mm objective lens, allowing for plenty of light to pass through and making night sky targets more visible. The multi-coated optics further enhance the viewing experience, ensuring a clear image of those targets. With a focal length of 1200mm, you can observe the finer details of celestial bodies, such as craters on the moon and features of other planets.
This powerful telescope offers up to 133x magnification, allowing you to observe celestial objects in incredible detail. With the included eyepieces, this level of magnification is perfect for viewing the moon and planets. You won’t miss out on any of the finer details.
It’s also well built and easy to use, a huge plus for those without bags of astronomy experience. However, you can get alternatives for a lower price, even if they don’t quite match the Skyline 6″ for quality of specs. We also like the Orion AstroView 90 (opens in new tab) a lot, for which this is a suitable replacement, however, it’s hard to find it in stock online.
(opens in new tab)
The Celestron Omni XLT 102 is aimed at intermediate-level skywatchers, particularly those who have mastered setting circles and know how to use the right ascension and declination coordinates on the supplied high-quality CG-4 German equatorial mount.
Featuring Celestron’s StarBright XLT coating to maximize light transmission, the Omni XLT 102 boasts high-quality optics and aspheric shaping technology to reduce spherical aberration, a visual defect in which incoming light is concentrated at select points.
As such, the Omni XLT 102, with its mix of aperture and f/10 focal ratio, is able to produce excellent views of the planets, from Jupiter’s atmospheric bands and moons, to Saturn’s rings and craters on the moon, showing great contrast between areas in shadow and those bathed in daylight. While there is a slight amount of color fringing, views through the optical system are outstanding.
The refractor comes with a 25 mm eyepiece, 1.25-inch star diagonal, heavy-duty stainless steel tripod, accessory tray, spirit level, Starry Night Special Edition software and a 6×30 finderscope.
Best astrophotography telescopes
(opens in new tab)
Celestron’s EdgeHD technology turns Schmidt-Cassegrain telescopes into high-quality astrographs with perfectly flat fields. The way that the Schmidt-Cassegrain optics focus light usually means that the focal plane — where the light comes to focus — is curved, but if you are imaging, your CCD camera’s sensor is flat. A curved focal plane on a flat CCD sensor results in field curvature, where stars at the edge of the field tend to blur. This is generally an unwanted effect for astrophotographers.
We were pleased to find, during our Celestron Advanced VX 8 EdgeHD review, that the optics in the EdgeHD negate the blurred edges, creating a perfectly flat field right to the edge of the frame for pinpoint sharpness across the whole image. The optical performance that the Celestron Advanced VX 8 EdgeHD delivers is impressive, with crisp and clear views with no optical distortion or false color.
As an added bonus, the optical tube assembly comes packaged with Celestron’s Advanced VX mount, which is tailor-made for imagers, capable of photographing across the meridian (an imaginary north-south line) without needing to do a meridian flip. The setup also performs periodic corrections to remove errors when tracking objects and also features an auto guider port.
The Celestron Advanced VX9.25 EdgeHD can carry a load up to 30 lbs. (13.6 kilograms) too, so the tube and all your imaging accessories are fully supported and stable. Also included are the standard NexStar+ hand controller, a 40 mm eyepiece, and access to Celestron’s SkyPortal app (opens in new tab) and Starry Night Special Edition software (opens in new tab). Check out our Celestron deals page to see if you can snap up a bargain.
(opens in new tab)
Sky-Watcher’s Skymax 150 is a great package for the price, with some models offering a high-quality equatorial mount for short-exposure astrophotography and long-exposure imaging. This well-constructed Maksutov-Cassegrain also comes with a single eyepiece with a focal length of 28 mm for a magnification of 64x.
Weighing in at 13.23 lbs. (6 kilograms), the Skymax 150 is suitable for most regular equatorial mounts — many makes and models will be able to take the load of both the telescope and extra accessories, including CCD or DSLR cameras, filter wheels and other such add-ons. For versatility in the type of mount you choose, a Vixen-style dovetail plate is supplied for a moderate price tag.
The Skymax 150’s optical prowess is outstanding, with no sign of optical distortion. The telescope is a great all-arounder, suitable for imaging everything from the planets to deep-sky galaxies and nebulas — and as you would expect for a telescope designed for giving great images. As an added bonus, the instrument is a breeze to use and accessorize.
The focuser is lovely and smooth to operate and the Skymax 150 keeps a good amount of fine focus once it’s been found — vital for those long imaging sessions.
Telescope types comparison
If your biggest question is, ‘which type of telescope type should I buy?’ let us help. Reflector vs refractor vs catadioptric telescopes: There are some key differences between how they work and how each type of telescope is helpful for different observations. Telescopes look visually similar from when the telescope was invented but there have been many improvements to both design and function over the years.
Before purchasing one of the best telescopes available, it is important to consider your desired outcome. Are you looking to observe distant star clusters, nebulas and galaxies? A reflector telescope is undoubtedly the most suitable option if the answer is yes.
Aperture: The diameter of the primary mirror or lens, where the telescope collects light.
Field of view: Area of sky visible through the eyepiece.
Focal length: A telescope’s tube length. Short focal lengths offer a wide field of view and a small image.
Focal ratio: Also known as the telescope’s speed. Small focal ratios provide lower magnifications, a wide field of view and a brighter image.
Magnification: The relationship between the telescope’s optical system and the eyepiece.
Alternatively, a refractor telescope is the best choice if you are mainly interested in seeing the moon and other planets in our own galaxy.
Another option would be a catadioptric telescope, which can work as a happy middle ground. Some models have computerized motors that make aligning and tracking targets easy and can even capture images for you, excellent news for astrophotographers.
The aperture size is one of the most important things to consider when purchasing a telescope, followed by the focal length. The main thing to remember here is that bigger isn’t always better.
It all comes down to what subjects you want to view. Shorter focal lengths, saf about 20 inches (500 mm), will provide a field of view for you to take in large areas of the Milky Way and showpieces such as the Pleiades (Messier 45) and Orion Nebula (Messier 42). Meanwhile, high-power objects like the moon, planets or double stars need a telescope with a longer focal length of about 80 inches (2000 mm).
If you can’t decide, there are plenty of compromises between aperture and focal length, but you must be willing to make a few trade-offs regarding the weight of your instrument, the field of view and its ‘power.’ Read on for what you can expect from the three major kinds of telescope: the refractor, reflector and catadioptric.
How does a refractor telescope work?
As their name suggests, refractors bend (or refract) the light that they gather to give you a view of your astronomical target. As telescopes go, they have a fairly straightforward assembly and consist of a main objective lens at one end that focuses light through to the other (the bit you look through).
Intuitive to use, the refractor is often a popular choice of instrument for novice astronomers since they require little maintenance and are usually affixed to the simple alt-azimuth mount, which allows the skywatcher to slew from left to right and up and down in order to locate the desired target. Being easy to use means that these telescopes are also simple to manufacture, making them cheaper to buy with price points increasing with aperture size.
Refractors are particularly good at giving highly magnified and high-contrast images. Because of this, they are ideal instruments to use when looking at solar system targets such as the moon and the planets. The best refractors usually have an aperture of two inches (60 mm) or more and will provide reasonable views of astronomical objects. If you’re looking for a larger aperture, then a three- or four-inch (80 mm to 90 mm) will suit you best.
The drawback of a refractor is that they can suffer from chromatic aberration, also known as color fringing. When a single lens doesn’t focus all of the colors emitted from a target object at the same point, bright objects such as the moon, Venus or Jupiter usually have a colored halo around them. Many refractors are manufactured as achromatic or apochromatic (also known as Extra Dispersion (ED) telescopes) to reduce this problem.
The achromatic refractor is cheaper than the apochromatic refractor and, combined with its efficiency, is often the type of telescope that novice astronomers go for. Even if you decide to go for the more expensive achromat, you’re still likely to get a stubborn degree of purple fringing around some targets.
Unless you’re a seasoned skywatcher and you can afford to go for the more expensive apochromat — which corrects for such an effect by using exotic glass for the lenses — this degree of color fringing will not ruin your observing experience to any great extent. If you decide to go for the expensive option, you will be stunned by the views you will get through these excellent telescopes.
Something to consider though: you might find that some apochromats come without a tripod, so you’d need to buy one separately along with any other accessories.
How does a reflector telescope work?
There are two common types of reflector telescope — the Newtonian and the Dobsonian. However, the way these instruments operate is exactly the same — they both use mirrors to reflect light to create an image of the object you’re looking at.
The Newtonian telescope comprises a curved-light collecting mirror, which can be found at the tube’s base. The light that hits this mirror is reflected back to the front of the tube, where a smaller flat mirror — orientated at 45-degrees — brings light to the observer who can see their chosen object.
The Newtonian can be found on alt-azimuth mounts, but you shouldn’t be too surprised to find this type of reflector is more popularly affixed to an equatorial mount, allowing the telescope to follow the rotation of the sky while being aligned with your hemisphere’s celestial pole. This reflector is a favorite in the amateur astronomy community due to its versatility by observing a wide selection of astronomical targets and allowing for astrophotography. With Newtonians, you can also buy a large aperture for less money — for instance, an eight-inch (203.2 mm) reflector would cost you less than a refractor with the same aperture, allowing you to get much more value for your money.
On the downside, the Newtonian doesn’t come hassle-free, especially regarding maintenance. You might find yourself having to have optical mirrors realigned as well as the mirror’s surfaces repainted since they can eventually become tarnished. If you choose to go for a reflector of this sort, you should always choose one with mirrors with a protective coating as they will last longer.
Some beginners to the hobby of astronomy might find setting up and using an equatorial mount tricky and that’s where the Dobsonian comes in. These telescopes give the capabilities of a reflector without the complexities an equatorial mount will bring since it employs an alt-azimuth mount. Dobsonians are very simple to use and can easily be pulled into orientation when looking at astronomical objects. If you’re not confident in navigating your telescope though, then GoTo or computerized Dobsonians and Newtonians (that slew to objects for you) are on the market — but at a higher cost.
Whatever reflector you choose, these telescopes are excellent for low-magnification targets such as galaxies and many types of nebulas.
How does a catadioptric telescope work?
To get the best of both reflectors and refractors, manufacturers developed the Schmidt-Cassegrain and the Maksutov-Cassegrain telescopes. These catadioptric telescopes generally correct issues found in refractors and reflectors.
The Maksutov-Cassegrain corrects the problem that the reflector experiences — an aberration effect called ‘coma,’ which can make objects look distorted and appear like they have a tail. This effect is reduced or banished with the combined efforts of a mirror and a corrector lens. The Maksutov is ideal for beginners or for those who don’t have the time (or money!) to complete any extensive maintenance on their instrument since the tube’s optics are sealed off.
This catadioptric is very robust and is the ideal family telescope. Packed into its short optical tube is a system that allows you to target higher magnification objects such as the planets, moon and double stars. You’ll be able to pick up a Maksutov for a very good price and, if you struggle to find objects and your way around the night sky, then both this type of catadioptric telescope and the Schmidt-Cassegrain can be found in abundance and equipped with a GoTo system.
What you get with a Schmidt-Cassegrain is very similar to the capabilities of the Maksutov. It will allow you to make general observations of planetary targets and stars. It is also possible to expand the telescope’s field of view with the help of corrector lenses, allowing you to view an even wider selection of astronomical targets.
The catadioptric telescope is also suitable if you want to try astrophotography, but combine this with their marked improvement on your standard telescope and you should expect a substantial rise in cost compared to standard reflect and refractors.
How we test the best telescopes
To guarantee you’re getting honest, up-to-date recommendations on the best telescopes to buy here at Space.com we make sure to put every telescope through a rigorous review to fully test each instrument. Each telescope is reviewed based on numerous aspects, from its construction and design, to how well it functions as an optical instrument and its performance in the field.
Our expert staff and knowledgeable freelance contributors thoroughly test each telescope. This ensures honest reviewing based on the telescope’s price, category, and intended use. For example, a 10-inch Dobsonian should not be compared to a 2.76-inch refractor, even though they may be the best in their own class.
We assess the ease of setup of both computerized and motorized mounts, as well as their reliability, accuracy, and noise level. Additionally, we decipher whether a telescope comes with appropriate eyepieces and tripods. We also make suggestions for any additional kits that may be beneficial for the best experience possible.
With complete editorial independence, Space.com are here to ensure you get the best buying advice on telescopes, whether you should purchase an instrument or not, making our buying guides and reviews reliable and transparent.