Best Telescope for under £100

Most folks start and end their journey into space with one of the top 15 best selling scopes on amazon. They all come in at under £100… some are pants, some are merely bad, none are good enough to give you that - wow - turn you into a nerd  moment. And yet it is possible to find an amazing telescope for under £100

Quick Link to my TOP PICK HERE

A Good telescope for a good price

For under £100 there are two types of telescope on the market. The Newtonian which relies on mirrors and the Refractor which relies on lenses. Mirrors have a big advantage over lenses because all the wavelengths of light bounce off the mirror in exactly the same way but when light passes through a lens the blue light is bent slightly more than the red light and so the light doesn’t end up in exactly the same spot. This is why stars viewed through cheap refractors tend to have blue halos around them. The geeks call this chromatic aberration.  So you might think that a small cheap Newtonian would perform better than a small cheap refractor.

Celestron Firstscope Review:

  • the mount is great

  • the mirror isn't great

  • the eyepieces are terrible

... at least its cheap!

How good is a Newtonian?

The second thing to watch out for is the secondary obstruction. It is a very annoying fact that reflecting telescopes have an obstruction. The light ripples as it passes the obstruction. Everyone says the bigger the obstruction the bigger the ripple and the worse the telescope gets. This is no doubt true but in my opinion there is another factor to consider and that is the overall size of the telescope itself. I remember Sir Patrick Moore saying that you shouldn’t bother with Newtonians thinner than 5 inches and having tested out various small newtonians for less than £100 I agree with the great man. I think the reason is because the light ripple from the obstruction buggers up quite a high percentage of the light hitting the main mirror of a small newtonain but a larger mirror has a comparatively smaller percentage of buggered up light hitting it!. This is my technical interpretation, make of it what you will 🤣

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Newtonians are nearly always fantastic but there are two things you need to watch out for. The first is the shape of the mirror. Spherical mirrors are easy to make but they are mostly rubbish. Parabolic mirrors are harder to make but if done well they are fantastic (FYI at long focal rations spherical mirrors and parabolic mirrors become almost indistinguishable which is why the classic Russian 150mm f8 Tal 2’s very precise spherical mirror works so well).

SkyWatcher 76mm Heritage  Review:

  • the mount is great

  • the mirror is good

  • the eyepieces are good

On paper this scope should be great but sadly it isn't. What's going on?

100mm mini dob is much better but still not as good as a good refractor:

Is it worth buying a cheap telescope?

So if cheap small Newtonians suffer from nasty light ripples and cheap small refractors suffer from chromatic aberration is there any point in buying a cheap telescope. The answer is undoubtably YES because some cheap refractors – not the ones you see topping the google searches -  are able to overcome the aberrations and deliver astonishing views.

Absolutely the best telescope for under £100

Back in the day telescope makers realised that if they used relatively weak lenses that didn’t bend the light too much they don’t suffer nearly so much from chromatic abberations. And as a bonus these lenses are relatively easy to make and therefore cheap. Of course if your making a telescope with a lens that doesn’t bend the light too much it needs to be long because it takes a long time for the weakly bent light to come to focus… this is not fashionable anymore and most folks prefer to buy more compact scopes but when the light in one of these long thin scopes does come to focus you get an AMAZINGLY crisp highly magnified view of whatever it is your looking at. Honestly the view I got of Jupiter through a £75, 60mm fat, 700mm long  celestron ABSOLUTELY knocked my socks off. This kind of scope is without doubt the best value telescope for viewing the planets.

The 60mm F12 scopes are sold by various companies but are probably made in the same factory in China. These are the best value telescopes for under £100. I am including extra links including this amazon link as I expect these will sell out very quickly.

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If you can buy one of these long refractors with the old school yoke tripod mount or even better an EQ mount then its much better than the modern cheap, plastic tripods which are rubbish. I totally feel like an old fart saying this but its true!!! You’d be better off with a decent camera tripod or one of these tripods.

The 70mm F10 refractors like this Skywatcher Mercury 707 are slightly better than the slighly smaller 60mm cousins, but most tip over the £100 barrier. 

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Best telescope for seeing Andromeda Galaxy and the Milky Way
(and still good on the planets)

If you want a budget scope that is good at cruising along the milky way and bagging some of the larger deep space targets like the Andromeda Galaxy and the Orion Nebula as well as being nearly but not quite as good at viewing the moon and the planets then you’re going to need to spend a little bit more than £100 on a classic 80mm f5 achro… it really is a winner, please watch the beginning of this video.

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EU customers will need tube rings to fix the omegon scope to the tripod

The Classic 80mm Achro...
(creeping above £100 now 🥺
but still amazing😄
if you get the right one.)

The Skywatcher Startravel-80mm (aka ST80) and the Meade Adventure Scope 80mm (and Meade 80mm infinity package - which comes with a better tripod) and the old Celestron ST80 and old Orion 80ST are  made by Synta in China. Apart from the labels and add ons these are the same scopes (BE CAREFUL don't buy the latest Celestron travel scope. It is - I believe - inferior ).  Each is a simple, cheap, two lens design called an achromatic doublet. Good 80mm achromatic doublets hit an optical sweet spot. Whilst larger achromatic doublet designs suffer from noticeable purple fringing this small 80mm scope controls the fringing well. The reason could be that the small 80mm lenses are easier to manufacture to very high standards or because the 80mm lens’ relatively low usable magnification is unable to resolve the fringing.  Either way this scope rocks and is a keeper even for mega nerds like me!

This little refractor will show you craters within craters on the moon, Saturn’s rings, Jupiter’s four Galilean moons, at least two of Jupiter’s bands and on a calm night the great red spot. But that's not all. This little scope’s speciality is sucking in lots of light from a wide area to reveal big, dim, wide field deep space nebula. With a low magnification eyepiece look for the faint but gobsmakingly colossal oval that is the Andromeda galaxy (M31) or the dazzling Seven Sisters star cluster (M45)  or the wisps of cloud around the Orion nebula (M42).  It is of course hard to see these in the city but this scope's small size and low price make it the perfect scope to sling into a rucksack and take somewhere dark.

View through the scope

Do I need a tripod?

Yes. In my video I used a good quality camera tripod. If you don't have a good camera tripod  already  then I have two budget recommendations depending which side of the pond you live. (NB: the  amazing value Meade Adventure scope comes with a very cheap tripod which I wouldn't use. For a little bit more I would get this package which has a much better tripod).

Can I get a small computerised GOTO mount and use this scope for Astrophotography?

Yes. Many will disagree but I've taken photos through this scope and those who disagree probably haven't! My first astrophotography video was using the 100mm diameter version of this  scope on a motorised alt azimuth mount. You can checkout the video here. You too will need a motorised mount to photograph deep space with this scope. Happily Sky Watcher recently released a lighter and better version of their alt az mount which I personally love.

Warning this Alt Az mount is fiddly. If you are interested in astrophtography with this telescope please check out this page about BUDGET MOUNTS

To attach your camera to the scope you might need a

nose-piece and adapter for

your camera

Does this scope's purple fringing ruin the shot?

Well purple halos around stars is a potential problem with this scope so I used a Baader Fringe killer filter on this shot of Andromeda taken with this cheap 80mm scope from Devon. 

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