Buying Guide - Telescopes
Find the right telescope to explore the wonders of the night sky at Australian Geographic.
There are countless marvels you can see in our galaxy with your unaided eyes, but when you are ready to see more a telescope is the only way to go. Whether you are looking for your first telescope or are interested in upgrading your current version, you will see there are a lot of different features and options available. Our team of avid astronomers created this buying guide to help you learn about the difference between refractors and reflectors, magnification, aperture, and everything else you need to know.
What is a telescope?
A telescope is an optical device designed to make distant objects appear closer.
There are a variety of telescope types. Some use an arrangement of lenses, while others use a combination of curved mirrors and lenses. The ultimate aim of all telescopes is to help improve your view of things that are far away, whether they be in the sky or on land.
What are telescopes used for?
Telescopes can be used to look at things in space such as stars, planets and even other galaxies. They can also be used for viewing terrestrial objects that are distant from you such as mountains, boats at sea or birds in a tree.
Telescopes collect lots of light, colours and finer details that the unaided human eye can’t see.
As an example, our unaided eyes can only see details about the same angular size of Jupiter’s width, however with a telescope we can resolve finer details like Jupiter’s Great Red Spot.
Telescopes can also record observations with cameras, allowing you to share your observations with the world!
What are the different types of telescopes?
The two main types of telescopes are refractors and reflectors. Refractors use lenses to magnify distant objects, whereas reflectors use curved mirrors. There is a third type knows as catadioptric or Cassegrain, which uses a combination of lenses and mirrors. Cassegrain telescopes combine the best qualities of refractors and reflectors in a compact design which is highly capable and portable.
Does size matter? Do I need to buy the biggest telescope?
Not necessarily! You should consider a combination of factors depending on what you want to see and how you want to use your telescope.
What are computerised telescopes?
The diameter of the telescope is important, as the bigger the aperture, the more light the telescope will be able to collect and focus. Ease of use, portability and technology should also be considered. A computerised and motorised telescope makes finding and tracking objects easier, while a compact telescope might be easier to assemble and transport. Telescopes with the latest wifi technology are great option if you want to control the telescope with your smart phone or tablet.
A computerised telescope is one that has an inbuilt power and database to make it easier to find objects in space.
What is aperture?
Computerised telescopes are often motorised, which means that a motor will move and aim your telescope at the object in space. It will then use the onboard computer to help track that object so it remains in view. Just remember that computerised telescopes need a power source, which is often a powertank or cable to connect to power.
Aperture is the diameter of the main lens or mirror of the telescope. The bigger the aperture, the more light that is collected and the sharper the image will be.
Which telescope is right for me?
A good beginner telescope is on that has a large enough aperture to allow more light and let you see more. Seeing more early on can ignite a lifelong passion for astronomy. Large aperture telescopes like a 114AZ or 130EQ are great for beginners as the aperture will let you see fine details and help you navigate the sky. Equatorial mount (EQ) will make it easier to track the stars and planets.
A good telescope for children is one that will keep them interested in astronomy, and science in general, for years to come. A 60mm or 70mm telescope is a good starting point, as is a 130EQ which has a larger aperture. Telescopes with a larger aperture are a good choice for a child who wants to track objects and is open to more complexity.
Advanced astronomers should look for a large aperture telescope of 8 inches or more. A computerised wifi telescope is an ideal advanced telescope, and there are a variety of optics quality and sizes to help you find the right telescope for your budget.
A refracting telescope is the best type for viewing terrestrial objects such as distant mountains or boats at sea. You can use a reflector, however the mirrors in reflector telescopes can turn the viewing image upside down and back to front unless you use additional adapters. If you are using your telescope for land viewing, make sure it has erect image optics to make sure the view appears the right way up.
Another option is a spotting scope, which is a telescope designed for land based viewing. You could also use a pair of binoculars to view terrestrial objects.
SHOP LAND VIEWING
Astrophotography is a popular aspect of modern astronomy which continues to grow as new technologies are developed. There are a few things to consider in astrophotography telescopes:
1. Tracking mount - choose a telescope with a solid motor-driven tracking mount, preferable German Equatorial.
2. Payload – how much weight can the telescope carry? Can it handle the weight of your camera?
3. Camera – are your using an imager, DSLR or CCD? Will you need additional accessories?
Thinking about these factors will help you select the right telescope to shoot fantastic astrophotography.
A reflector telescope uses a single or a combination of curved mirrors that reflect light and form an image. The AstroMaster 130 is highly recommended if you want a manually controlled reflecting telescope, and the NexStar 130 SLT is a great option if you are looking for a computerised reflector.
A refractor telescope uses a lens as its objective to form a large image and they are often longer in length than reflector telescopes due to the lens. The Explorascope 70AZ is one of the most popular telescopes as it’s a great entry level telescope for beginners and children, it’s also very easy to use and impressive to display in your house!
A Cassegrain telescope uses a combination of a primary concave mirror and a secondary convex mirror. This design allows the focal point to be at a convenient location behind the primary mirror, and they alwo allow for a mich longer focal length within a shorter tube design. The NexStar 4SE is a one of the best options, featuring a Maksutov Cassegrain design optical tube mounted on a computerised mount.
A Dobsonian telescope is an alt-azimuth Newtonian design that offers a larger aperture at a lower cost, ideal for amateur astronomers. The smaller sizes are suitable for children as they are stable, lightweight and portable. A great grab-n-go telescope.
Ideal for astronomers who want automatic tracking, quick and easy alignment, and access to a database of thousands of coordinates. Most computerised telescopes com with wifi control, inbuilt lithium batteries and good-sized optics which enable you to observe deep space objects.
Do I need any accessories?
Accessories are an easy way to maximise your viewing experience and tailor your telescope to suit your needs. Choosing a range of additional eyepieces will allow you to change magnification from a wide field of view to a more zoomed in, selective range, giving you more control over your viewing experience. Other accessories like filters help with viewing planets or the moon. You will need powertanks to power computerised telescopes, and you can use a wifi adapter to convert computerised telescopes into wifi controlled telescopes. A StarSense camera accessory automatically aligns your telescopes and helps you start observing space objects sooner. There are plenty of options!