Telescopes

Amateur astronomy can be a fantastic hobby that anybody can enjoy. Looking into the sky on a clear night can be amazing on it’s own, but getting up close and personal with our planets, the moon, and even other galaxies is something else. The problem is, choosing your first telescope can be a very daunting task. Telescopes can get quite complicated, and there is a lot of terminology used to describe telescopes that most people who are new to astronomy don’t really understand.

Don’t worry, we’re here to help! In this guide, I have started off by taking a look at some great telescopes for beginners to consider. Then I have answers for a couple of questions you might have relating to the cost of buying a telescope and what you can realistically expect to see. Next, there is an in-depth guide to help you understand how telescopes work and the differences between different models. Finally, I have included some information and recommendations for choosing a telescope for a specific purpose.

The Best Telescopes

If you are serious about getting into amateur astronomy, I would highly recommend reading all of this guide. Not only is it invaluable to have an understanding of telescopes when deciding on which one you should buy, but it’s also really interesting to learn about how they work and the different parts. But if you are looking for a quick answer, the telescopes below are all excellent choices.

Zhumell Z130 – Best Bang for Your Buck

The Zhumell Z130 is a great telescope for beginners who don’t want to spend a huge amount on their first telescope but still want something that’s fairly powerful.

The 5″ aperture on the Zhumell is really quite large for the price giving you a lot of power for a low price. The focal length is relatively short at 650mm which means it’s a good choice for viewing deep space objects. (The f/ratio of this telescope is f/5.) However, with a more powerful eyepiece or a barlow lens, this telescope is also great for viewing planets and the Moon. Overall, a great all-round telescope for beginners.

Find it on Amazon

Orion SkyQuest XT4.5 – Budget-Friendly, Good for the Moon & Planets

The Orion SkyQuest XT4.5 has a slightly smaller aperture than the Zhumell at 4.5″. This means it isn’t quite as powerful but isn’t far behind. However it has a longer focal length at 900mm giving it an f/ratio of f/8. The advantage of the longer focal length means you won’t need as powerful an eyepiece for higher magnification because the telescope itself will be doing a lot of the work.

This is another great telescope for beginners. The Dobsonion mounts make them easy to set up and use, and the long focal length makes them ideal for viewing planets and the Moon.

Find it on Amazon

Orion SkyQuest XT6, XT8 & XT10 – Larger Aperture = More Power

The Orion SkyQuest XT6, XT8 & XT10 telescopes are the big brothers of the XT4.5. All of these telescopes have a relatively long focal length of 1200mm. The main difference between them is the aperture which is 6″, 8″, and 10″ respectively (hence the names).

These telescopes are a good choice for beginners due to the easy-to-use Dobsonion mounts, however you should keep in mind that these telescopes – particularly the XT10 – are rather large and quite expensive.

• Orion SkyQuest XT6 – Find it on Amazon
• Orion SkyQuest XT8 – Find it on Amazon
• Orion SkyQuest XT10 – Find it on Amazon

Celestron AstroMaster 70AZ – Budget Friendly & Low Maintenance

The Celestron AstroMaster 70AZ is a telescope to consider if you’re on a very tight budget and want something that’s low maintenance. Unlike the previous telescopes, this one is a refractor which means it uses a lens rather than mirrors. The advantage is that misalignment isn’t as much of a problem, and they are easier to clean and maintain.

The downside is refractor telescopes don’t give you as much bang for your buck. The 70AZ might be fairly cheap, but it has a small aperture of just 2.76″. However, this telescope has a relatively long focal length at 900mm making it a good choice for planets and the Moon.

Find it on Amazon

Celestron AstroMaster 90EQ – Low Maintenance

The Celestron AstroMaster 90EQ is another refractor telescope to consider. With a 3.54″ aperture, you’re still not getting as much bang for your buck as you would with a reflector telescope, but it isn’t bad for a refractor at this price.

Like with the AstroMaster 70AZ, this is a telescope to consider if you want low maintenance. Due to the low aperture but fairly high focal length of 1000mm, this telescope is great for viewing planets and the Moon.

Find it on Amazon

How Much Should I Spend on a Telescope?

The first thing you might be wondering is, how much should I spend on a telescope? You’ve probably seen the cheap telescopes you can pick up in toy shops for under $50, but then there are huge and incredibly powerful telescopes that can cost thousands of dollars.

Well, luckily, you don’t need to spend thousands of dollars to get a good quality telescope that can give you some amazing views. However, I would recommend spending at least a couple of hundred dollars if you plan on taking this hobby somewhat seriously. If you spend much less that this, you’re going to find yourself with a telescope that is underwhelming. It will likely either have poor optics so you can’t see much, or an unstable mount which will be really frustrating to use. If you have the budget, say around $500 – $600, telescopes in this price range will give you more power and the ability to see more detail and more objects in the sky.

What Can I Realistically Expect to See?

The second thing you’re probably wondering is, what can I realistically expect to see? The important thing you need to realise is that many of the photos of space you will have seen have been taken through huge, incredibly powerful telescopes like the Hubble telescope. Unfortunately, you’re not going to get this kind of quality with your own telescope.

What you can expect to see depends on three main factors:

• Your budget – the higher your budget, you will be able to afford more powerful telescopes which will allow you to see more detail and more objects.
• Atmospheric conditions – if you use your telescope on a clear night with no light pollution, you will be able to see a lot more.
  

• What you want to see – you can see some great detail in the Moon, even with a fairly cheap telescope, but further away objects won’t look quite as impressive.

It’s important to understand the points above, but I get that you probably want to see pictures of what you can actually expect to see. The video below shows Venus, Jupiter, and Saturn through an Orion Skyquest XT8 plus. (Very similar to the Orion Skyquest XT8.)

The moon is much closer to us than the planets so you can see a lot more detail. These images are also taken through an 8″ Dobsonion telescope.

A Guide to Telescopes

There are lots of different aspects to a telescope. Different types, sizes, mounts, etc. In this guide, I have broken down how all of these differences affect the telescope.

Types of Telescope

Refractor telescopes were the first to be invented. They use a lens to gather and focus light and are what most people think of when they imagine a telescope; long and thin with the eyepiece right at the end. The main advantage of refractor telescopes is that they are easy to maintain. After the initial alignment of the lens, they won’t need realigning very often, and they are sealed from the atmosphere so don’t require regular cleaning. However, refractor telescopes suffer from chromatic abberation. This is when you get a rainbow effect around an object, similar to when you shine light through a prism. They can also get quite expensive, especially as the aperture size increases.

Reflector telescopes use mirrors to gather and focus the light. There is a large, curved mirror at the bottom of the telescope which reflects the light to a second, smaller mirror near the eyepiece. The advantages of reflector telescopes is that they don’t cause chromatic abberation like refractors do, and they are cheaper to manufacture so you can usually get more bang for your buck. The downside is they require more maintenance. It’s easy for misalignment of the mirrors to occur, and they require frequent cleaning. They are also prone to diffraction spikes which is where you get spikes of light extending from bright objects like stars. Reflector telescopes are only suitable for observing space and are not for terrestrial use.

Catadioptric telescopes use both lenses and mirrors to gather and focus light. They are essentially a hybrid of refractor and reflector telescopes. The advantage of these telescopes is that they have the optical benefits of both lenses and mirrors and cancel out the disadvantages. They are also generally very portable. The downside is that they can be very expensive. They also lose some of the light due to the secondary mirror getting in the way. Like, reflector telescopes, they are only suitable for observing space and are not for terrestrial use.

Aperture

The aperture of a telescope refers to the diameter of the lens or mirror. A larger aperture allows the telescope to gather more light which gives you a brighter and sharper image. It also means you can use higher magnification and still retain a good quality image. Technically, you can use any magnification on any telescope, but if you try to use too much magnification with a small aperture, the image quality will be poor. There’s no strict rule, but a good guide is for the magnification to be no higher than 40x the aperture in inches.

A larger aperture will always produce a better quality image, but as the aperture size increases, so does the cost and weight of the telescope. If you want to view deep space objects like galaxies and nebulae, a large aperture is important because they are so far away and you want to gather as much of their light as possible. But for brighter and closer objects, like the moon or the planets in out solar system, the aperture size isn’t quite as important and you will want to pay more attention to the focal length.

Magnification

The magnification of a telescope is determined by the focal length of the telescope and the focal length of the eyepiece.

The focal length of a telescope is the distance between the lens or mirror and the eyepiece; basically how long or short the telescope is. To work out the magnification, you divide the focal length of the telescope by the focal length of the eyepiece. For example, if a telescope has a focal length of 1250mm and you use a 10mm eyepiece, the magnification will be 125x.

Technically, you can achieve any magnification regardless of the focal length by changing the eyepiece. For example, if you have a shorter telescope, say 625mm, and you used a 5mm eyepiece, you would also get a magnification of 125x.

So, why choose a telescope with a long focal length?

The advantage of a telescope with a longer focal length is that even relatively poor quality eyepieces will still work well. To achieve the same magnification, a shorter telescope will need to use a more powerful eyepiece, and high quality, powerful eyepieces can be quite expensive. With a longer telescope, the telescope itself will be responsible for much of the magnification, so the eyepiece doesn’t need to do as much work. Longer telescopes are usually a good choice for viewing objects like the moon and the planets in our solar system.

The advantage of a telescope with a shorter focal length is that they have a wider field of view and they are more portable. If magnification isn’t as important, and you will be viewing deep space objects like galaxies and nubulae, telescopes with a shorter focal length are a better option. And you can still get higher magnification by using a more powerful eyepiece, it just isn’t as ideal as using a longer telescope.

The relationship between the aperture and focal length is called an f/ratio. The f/ratio is calculated by dividing the focal length by the aperture. I would consider a telescope with an f/ratio of f/4 or f/5 to be short, f/6 to f/10 to be mid-range, and anything over f/10 to be long.

Eyepieces

We’ve already looked at how eyepieces in conjunction with focal length determine magnification, now let’s look at how eyepieces work and the different types. Telescopes usually come included with eyepieces, but often they are not great quality, and you will probably have to purchase additional eyepieces if you’re looking for a specific magnification or field of view.

Just like telescopes have a focal length, eyepieces have their own focal length which is measured in millimetres. The smaller the focal length of the eyepiece, the higher the magnification. (Remember, to find the magnification, you divide the telescope focal length by the eyepiece focal length.)

Each eyepiece has an apparent field of view. This is the number of degrees of the sky it appears you are viewing when you look through the telescope. (Of course the actual field of view will be much smaller because you are zooming in on a small section of the sky.) Standard eyepieces usually have a 45° field of view, but you can also get wide angle eyepieces which are 60° or more. For viewing things like the moon and planets, I would stick with a standard eyepiece, but for deep space objects like galaxies and nebulae, you might prefer a wide angle eyepiece. To calculate the true field of view (the actual number of degrees of the sky you will see), you divide the apparent field of view by the magnification.

Another important aspect of eyepieces is eye relief. This is the distance from the eyepiece to the observers eye. Eyepieces with a short eye relief can be quite uncomfortable to use, especially for people who wear glasses. Generally, the more powerful the eyepiece, the shorter the eye relief.

There are two standard eyepiece sizes you can buy: 1.25″ and 2″ (there is a third size, but it is largely discontinued). Most telescopes accept 1.25″ eyepieces, and these eyepieces are usually cheaper. Some telescopes accept 2″ eyepieces and usually come with an adaptor to also accept 1.25″ eyepieces. 2″ eyepieces are generally more expensive.

Barlow Lenses

Barlow lenses can be placed between the telescope and the eyepiece to increase magnification even further; usually by two or three times. Not only do they allow you to increase magnification, but they also allow you to double your magnification options. Let’s say you have a telescope with a 1000mm focal length and two eyepieces: 10mm and 4mm. With these eyepieces, you have options for 100x and 250x magnification. If you also have a 2x barlow lens, you will also have the options of 200x and 500x magnification.

Barlow lenses can be great, but you have to remember that too much magnification can be a bad thing. If your telescope has a relatively small aperture, then using too much magnification will give you a dim and poor quality image. As I mentioned earlier, there’s no rule for how much magnification you should use for a particular aperture, and a lot of it depends on the viewing conditions and what you are looking at. But a reasonable guide is for the maximum magnification to be no more than 40x the aperture in inches. For example, if you have a 4″ aperture, you wouldn’t want to go much higher than 160x magnification.

Barlow lenses come in the same sizes as eyepieces: 1.25″ and 2″, so make sure you choose the right size of barlow lens that is compatible with your telescope.

Mounts

Mounts are very important when it comes to telescopes. Even if a telescope has really good optics, a poor and unstable mount can completely ruin your experience. Mounts are used to keep the telescope steady and track objects in the sky. There are two main types of telescope mount:

Alt-azimuth mounts are simple two axis mounts. They can be moved left and right, and up and down. They work in the same way as standard camera tripods. The advantage of these mounts is that they are very easy to setup, and the telescope eyepiece should always be in a comfortable position. The downside is that they don’t compensate for the rotation of the earth like equatorial mounts, which means they aren’t ideal for viewing deep space objects or astrophotography. However, they are fine for viewing the moon or the planets in our solar system.

Equatorial mounts are more complicated. In these mounts, one of the axis is parallel to the earths rotational axis. This means that the image will always stay consistent and not rotate. The downside is that when the object you are viewing passes the meridian line, you will need to flip the mount which interrupts valuable viewing time when the object is at the optimal point. As the mount moves, it can also put the eyepiece in awkward positions on reflector telescopes. Equatorial mounts can be a pain to setup because they need to be aligned with the earths rotation. However, despite these drawbacks, equatorial mounts are still the best option for viewing deep space objects and astrophotography.

Some mounts have comptuers built in. These are called Goto mounts and can be either alt-azimuth or equatorial. Goto mounts can save you a lot of time by quickly pointing to specific objects in the sky. Whether or not you want this feature is down to personal preference, but there are a few things to consider. Firstly, they are more expensive, and you could put the extra money towards a more powerful telescope. Secondly, for many people, locating the objects on your own is part of the fun and it can feel very satisfying when you finally find what you were searching for. However, if you just want to see specific objects as quickly as possible, or perhaps you will be using the telescope as a family and you don’t want to be spending too much time faffing around, Goto mounts can be very handy.

Finderscopes

Finderscopes are like mini telescopes that sit on top of the main telescope. When you look through a telescope, you are only looking at a tiny part of the sky and it can be very difficult to find the object you are looking for. Finderscopes have either no magnification or a small amount of magnification, and a crosshair in the middle to show where the main telescope is pointing.

Even if you have a Goto mount, finderscopes can be useful. Goto mounts need initial alignment and a finderscope will make this process much easier.

Finding the Right Telescope for You

There are lots of different telescopes out there. Different types, different mounts, different sizes. etc. In this section, I want to go through what to look for in a telescope for different situations and hopefully help you find the best telescope for you.

For each category, I have made a few recommendations. There will be some crossover because most telescopes are great for multiple purposes. There are also some excellent telescopes which aren’t mentioned, but I didn’t want to overwhelm you with too many options so I picked out some popular and highly rated models.

Best Telescopes for Beginners

If you’re buying your first telescope, there are a few key points to consider.

You will want the telescope to be nice and easy to setup and use. For this, I would recommend a telescope with a Dobsonian mount (these are a type of alt-azimuth mount). All of the telescopes in the list below are Dobsonian.

You might be tempted to go for a cheaper telescope to start with, but I would advise against this. If you do, you will most likely end up with a weak telescope and you will be let down by what you can see with it. Or you will end up with a telescope with a poor quality mount that won’t keep steady and will make for a very frustrating experience. If you develop a passion for amateur astronomy, you will very quickly want to upgrade a cheap telescope.

However, it’s also understandable that you won’t want to spend too much on your first telescope. Reflector telescopes are great because they are cheaper to manufacture than catadioptric and refractor telescopes and offer excellent bang for your buck. For a couple of hundred dollars you can get a good quality Dobsonian reflector telescope.

Great beginner telescopes to check out:

• Zhumell Z130 (reflector) – 5″ aperture (very good for the price) and 650mm focal length. Easy to use with a Dobsonion mount. Includes a finderscope to help target objects. Great bang for your buck. – Find it on Amazon
• Orion SkyQuest XT4.5 (reflector) – 4.5″ aperture and 900mm focal length. Slightly smaller aperture than the Zhumell, but longer focal length so better for higher magnification. Great for viewing the moon and planets. Includes a finderscope. – Find it on Amazon
• Orion SkyQuest XT6 (reflector) – 6″ aperture and 1200mm focal length. The XT6 is a great beginner telescope if you’re willing to spend a bit more. The larger 6″ aperture makes this telescope more powerful than the Z130 and XT4.5. – Find it on Amazon
• Orion SkyQuest XT8 (reflector) – 8″ aperture and 1200mm focal length. The XT8 is the big brother of the XT6 and is even more powerful with an 8″ aperture. This telescope is a bit more expensive though, and not as portable. – Find it on Amazon

Best Telescopes for Viewing Planets & the Moon

For viewing the moon and the planets in our solar system, you want to look for a telescope with a longer focal length. A longer focal length will help you to get more magnification without needing powerful eyepieces. Ideally, look for a telescope with an f/ratio of f/8 or higher.

However, aperture is still important when you are viewing planets and the moon. You should try to get a telescope with as large an aperture as you can afford and is practical. A larger aperture will give you more power and the ability for higher magnification whilst keeping a good quality image.

Great telescopes for viewing planets and the Moon:

• Celestron AstroMaster 70AZ (refractor) – 2.76” aperture and 900mm focal length. If you really don’t want to spend a lot, this telescope can be a good choice. But the small apperture really limits the detail you will see. Because it’s a refractor telescope, it doesn’t require much maintenance and is easy to use. – Find it on Amazon
• Orion SkyQuest XT4.5 (reflector) – 4.5″ aperture and 900mm focal length. Decent sized aperture, reasonable priced, and it has a long focal length which is ideal for viewing planets and the Moon. – Find it on Amazon
• Celestron AstroMaster 90 EQ (refractor) – 3.54″ aperture and 1000mm focal length. Decent sized aperture for a refractor telescope at this price and a long focal length makes it great for planets and the Moon. – Find it on Amazon
• Orion SkyQuest XT8 (reflector) – 8″ aperture and 1200mm focal length. A fairly large aperture and long focal length gives this telescope a lot of power and magnification potential for viewing planets and the Moon. – Find it on Amazon

Best Telescopes for Galaxies & Other Deep Space Objects

If you want to view galaxies and other deep space objects, aperture is key. Because these objects are so far away, they are very faint in the sky. You want your telescope to be able to gather as much of their light as possible, so you want to go with as large an aperture as you can. I would recommend a reflector telescope because they will give you the largest aperture for your money.

A wider field of view is preferable for viewing deep space objects, so unlike if you want to view planets and the Moon, you don’t necessarily need a long telescope. The most important thing is the size of the aperture.

Great telescopes for viewing galaxies and other deep space objects:

• Orion SkyQuest XT6 (reflector) – 6″ aperture and 1200mm focal length. Decent sized aperture for the price. – Find it on Amazon
• Orion SkyQuest XT8 (reflector) – 8″ aperture and 1200mm focal length. The XT8 is the big brother of the XT6 so a bit more power for a higher cost. – Find it on Amazon
• Orion SkyQuest XT10 (reflector) – 10″ aperture and 1200mm focal length. Even larger aperture than the XT8 which means more power. Keep in mind as the aperture size increases, telescopes become less portable. – Find it on Amazon

Best Telescopes for Kids & Families

Amateur astronomy can be a great hobby for the whole family to enjoy. However, it can be very easy for everyone to lose interest if you buy an inadequate telescope that doesn’t allow you to see much, or if you buy a telescope that’s too complicated and causes everyone to get bored as you try to work it out.

A 6″ Dobsonion reflector telescope is a great option for kids and families. Powerful enough to get some great views, but not too large and cumbersome. Dobsonion mounted telescopes are easy to setup and use so they shouldn’t cause too much down time. An 8″ Dobsonion telescope is also a great choice which will allow you to see even more, but of course it will be slightly larger and more expensive.

• Orion SkyQuest XT6 – 6″ aperture and 1200mm focal length. – Find it on Amazon
• Orion SkyQuest XT8 – 8″ aperture and 1200mm focal length – Find it on Amazon

Conclusion

I hope this guide has helped you! Amateur astronomy can be an extremely enjoyable hobby, but it isn’t easy picking a telescope. If you’ve got to the end of this guide, you should have a good idea of the differences between all the telescopes and who they are best suited for. The biggest thing to remember is that usually, aperture is key. The aperture is what gathers the light and the bigger it is, the more powerful the telescope, and the more you can see!