As a young lad, my older brother was doing a degree in astrophysics.  At one point he bought himself a quite expensive Meade telescope.  I wasn't really interested in it, and I can only really remember a single demonstration when we first got it.  We took it out into the back yard, had a quick look at the Moon and, admittedly, the lunar craters were impressive but the hassle to get the scope that far along the process seemed very long-winded, especially given the cost.  My brother went on to use the telescope for casual use, bringing it to youth camps that he ran, but I hadn't seen it or used it again in the 10+ years since I moved out of the family home.

Later, I happened to mention that I liked the idea of some casual astronomy - scientist, geek, it seemed to fit as a hobby and I have more than a passing interest in the Mars missions and similar achievements.  I've always lived in cities, so I've never really seen much of a sky at all.  Honestly, until only the other year, I'd never seen a planet with the naked eye.  Sure, I could recognise The Plough and a few others if it was a clear night, but pretty much it was something that I would have liked to know more but never had the equipment or inclination to pursue it.

One night, however, I was driving a car full of Italians to Scotland.  Because of the timing and the length of the journey, it was most sensible to drive through the night and stop as little as possible.  I was quite happy with such an enormously long drive, and there were other drivers present to take over if necessary, but I quite enjoy just driving along.  I'm not sure my passengers shared that opinion as they were all asleep within an hour or two and only woke up when we arrived at our destination.

But, as we crossed into Scotland and got out into the highlands, there was complete darkness, empty roads and a lovely near-full Moon.  And just beside and beneath it, a light.  While driving, it's quite difficult to pay attention to the scenery, but it so happened that there was a long, straight, empty stretch of road that led for miles and directly in front was the Moon and this light.  It took me a while before I paid the light any specific attention - there are lots of lights on major motorways, and lots of glass and mirrors in a car - but I soon realised that the object so bright was fixed in the sky.  I assumed it was a helicopter, or balloon, or some other fixed aircraft (being from the city, yes, this was my first thought), but it was then obvious that it was staying so perfectly still for too long and I never seemed to approach it.

At this point, the light had caught my interest and I slowed where convenient and tried to get the best (but safest!) look at it that I could.  And then I realised, it must be an astronomical object.  It was too big and bright to be a star.  It was too coloured and large to be an artificial satellite, a sort of pale reddy-yellow.  I took a stab in the dark at this point, and my primitive prior knowledge of astronomy kicked in.  Venus?  It's surely not one of the further-away gas giants as it's just too damn bright.  It had to be Venus.  After about 10 minutes of casual and fleeting observation, I'd convinced myself it was Venus (actually, I was convinced it was a planet, and the information I had in my brain at the time only presented Venus as something you might see with the naked eye).

After a while, I discovered that I was enjoying this little discovery of mine.  I'd seen a planet in the sky, for the first time (the first time I was able to identify one, anyway).  This must have been how the ancients felt!  (Well, probably not, but that's what you think as a modern man).  After a while, the excitement was too much and I nudged awake my girlfriend in the passenger seat.

"Look, look, see that?  I think that's Venus."

"Yes, dear." (mumbled sleepily).

Of course, my girlfriend is from a rural Italian town where, when the lights go out, you can see just about everything in the sky.

"But it's Venus!"

"Yes, okay, it's Venus" (turns over, starts snoring again).

And the only other people present don't speak English at all, and come from the same rural Italian upbringing.  I kept watching it when I could, though, and found it fascinating.   I was able to observe it for over an hour, just by the sheer luck of driving North on a long, straight, dark, empty road while it was in the North.  My companions later found it quite amusing that I'd never seen it before and said that, yes, it was probably Venus.  Of course, by the next night, it was barely visible at all and in the Scottish weather, it's hard enough to see the clouds themselves sometimes, through the fog, mist and rain, but that just meant that I was able to have the time in a quiet country pub to download an astronomy app and confirm that it had, in fact, been Venus that I'd seen.

How can something like that be there, that bright, in the sky and not cause comment?  I was quite taken with my discovery, although my companions were thereafter keen to tell me about the "shooting stars" that they saw almost every night up in the Italian mountains, and everything else they could to annoy me (including fireflies - another thing I've never actually seen without David Attenborough narrating).

Obviously, though, when my girlfriend next struggled to think of a present for a special occasion, she bought me a telescope.  Thus started a little trip back into the world of amateur astronomy, but this time with my own interest and equipment.

On receipt of the telescope, it was only sensible to read up on it a little.  Being a geek, that doesn't mean buying books but trawling the Internet and interrogating Wikipedia.  And soon, I'd learned a lot of new terminology and knew roughly what I was holding in my hands.  It's at this point that you have to decide just how far to take a hobby.  Personally, I flit between hobbies quite often, but I think it's great when you get into a hobby to find out about it, pick a cost limit, sink some time into it but not dedicate your whole personal life to it.  It's too easy to fall into the trap of spending thousands of pounds on equipment and being no better off than anyone else because you don't have the time/skill/inclination to actually use it.  It's a phenomenon I see a lot of in "enthusiast" circles, for everything from gaming PC's to motor cars, keeping fish to photography.

At this point, I made a few decisions.  My first thought on reading about so-called "Go To" telescopes was to discount them.  They basically do all the work for you and use computers and GPS and clever imaging algorithms to automatically set up your telescope to point and follow anything you want.  That I equated with those "amateur anglers" who have sonar, line warning alarms, and all the other gumph that turns a hunting-based sport into nothing more than a day out pressing buttons.  "You" didn't catch a fish, at all.  The computer did it for you.  That's couldn't be what astronomy was about, surely?  If I worked in an observatory, I wouldn't want to spend my life finding things, but as an amateur surely finding those things is the fun of it?

I also discounted the possibility of viewing nebulae or anything too fancy.  I would save that for any advanced stage, if I got that far, and start with larger, simpler, brighter, more visible objects.  You can't miss the Moon but I still remember getting to see the craters on it from my brother's telescope, and it was a pretty interesting thing to look at even when I wasn't interested in astronomy.  That would be my first target and then, after that, Venus again, and then see how things went.

And I was surprised, in all this reading, at quite how simple an astronomical telescope design could be.  Basically the telescope is literally nothing more than a tube with mirrors (yes, some of them use lenses exclusively, but even that I see as "more complex" than just a mirror in a tube).  I knew the theory of Newtonian telescopes already (those with two mirrors - one big one at the bottom of the tube and one small one, angled at 45 degrees, at the top.  The light comes down the tube, passes by the angled mirror, bounces off the end mirror, bounces back onto the angled mirror, which reflects it out the side of the tube where you can see it.  The second mirror "gets in the way" of the first mirror but because it's such a small obstruction in comparison, it doesn't matter and you do not see a "shadow" in the final image).

Why are they designed like that?  In astronomy, what matters most is the amount of light you can receive.  Things in space are very, very, very far away and they are usually throwing out light in all directions.  By the time you take a Sun's worth of light, and split it up into the huge number of directions it can take, and spread that light over millions of miles of intervening space, it looks less and less and less bright until - when you're far enough away - it's just a pin-prick of light that disappears even under a thin cloud.  So you want to collect as much of the light from the thing you're looking at as possible.  You can't magically "magnify" the amount of light you see - that's just determined by how much light the star gives out, how far away you are, and how much the light is spread out.  Think of a star as giving out a ball of light - if the ball was tiny, but you have some fixed amount of plastic it would have very thick walls.  But if the ball is MILLIONS of miles wide, still from that same amount of plastic, it would have to be less than paper-thin.  To get "more plastic" (i.e. more light) at a vast distance, you have to gather up a much larger section of the ball.  Similarly with telescopes, if you want to see objects that are dim, or very far away, you want to collect the light that is put over a much bigger area.  This will let you "see" a distant object more brightly as a result.   So a wider tube actually makes things brighter, which is somewhat counter-intuitive.  This is why the big huge telescopes you see on the top of mountains looking into the depths of the universe ARE so huge - size matters.

But why reflect off a mirror and not go through a lens?  Well, some telescopes do - even at the higher end (and almost all telescopes do eventually, as you'll see later).  However, lenses are made of solid matter, which the light has to pass through.  Invariably this means that the lens somewhat darkens the image, and distorts it, no matter how crystal clear it appears or well-made it is.  And we just spent so much time making it bright, that making it dimmer than necessary is a waste of time.  With the right shape of mirror, we can still gather that light, and put it where we want, but the light doesn't have to "go through" quite so many solid objects.

What's also useful in a telescope is the magnification.  However, this doesn't mean that a telescope that offers a million-times magnification is any good to us at all.  The light from a distant star travels possibly millions of light years, in "straight" lines.  A tiny, tiny portion of it passes through the hole at the end of your telescope, makes it down to the bottom of the tube without hitting anything (like the side-walls of the tube), gets bounced back and forth across mirrors but, while it's bouncing off mirrors, it is also being focused to a smaller point.  If your telescope is as wide as possible, like we need it to be, all that information from all that light cannot "fit" into your eye for you to see.  It's too large.  It's like trying to fit a small plate into your eye socket.  So by focusing the light, you are shrinking it down to occupy a smaller space (ideally the surface area of your eye's retina).  This, also, happens to make the object brighter than it would otherwise be.  We are shrinking, say, a small dinner plate's worth of light into the size of your eye, which makes it brighter than it would otherwise appear.

Because of this factor, the ratio between the width of your telescope's tube, and the length of the path it takes inside the telescope correspond to two things.  The "magnification" of the final image (i.e. how big that 1700km of Moon looks on the back of your eye), and the amount of sky you can actually see (if you magnify something, obviously you see "less" of the overall object through your eye/magnifier, but the small spot you do see is given to you in greater detail).  This directly impacts the detail you can perceive, and the brightness you can gather.

Obviously, when looking at an object a billion miles away, we'd like it to be bright enough to see, and detailed enough to study, so the combination of the width of the top of your tube (the "aperture") and the length of the tube overall (more accurately, the distance the light takes from the initial "bounce" off the back mirror to your eye, called the "focal length") directly correlate to the quality and brightness of the final image that you can see with it, and even whether you can see anything at all.

It's here that you fully realise the reason for the classic "Newtonian reflector" telescope design.  You couldn't hold a 200mm-wide, 1m-long telescope of the kind you might imagine Nelson would have used to "see no ships" up to your eye very easily, it would be too clumsy (unless you're Jack Sparrow).  It would also have some HUMONGOUS lenses inside it, each of which would distort and darken the final image.  And it would have to be quite long in order to focus that amount of light down to the point of your eye.

So a mirrored-reflector design cuts through all these problems by the simple use of a tube, two mirrors, and some clever design.  Newtonian telescopes are one of the more practical telescopes with the longest "focal length", and can be as wide as you like because you don't have to hold them up to your eye in order to see upwards (you're already reflecting the light wherever you want, so most Newtonian telescopes reflect it somewhere convenient for you to put the telescope on a tripod or stand, rather than as a tube extending from your eye directly towards the star you want to look at).  They also require no specialist glassblowing skills to make one.  Just a shiny surface, with a slight curve, that is manipulated and positioned enough to catch the light coming down an almost-empty tube and shine it somewhere else.  And, yes, you can quite literally make a Newtonian telescope out of a cheap plastic flexible mirror (so you can aim its reflection) or two, and a big tube.

Now, in practical terms, an amateur may well wish to start cutting Pringles' tins up and experimenting, and there's nothing wrong with that.  But when starting a hobby, it's often easier - if nothing else, to avoid classic mistakes and problems - to buy something cheap and amateur to get an understanding of the thing you're trying to achieve anyway.  And the fact is that telescopes can be stupidly expensive, and stupidly cheap.  Again, splashing out on the "best one" is probably the worst thing you can do as an amateur, and professionals in every field I've ever dipped my toes into fail to understand this ("You want to program computers?  Well you should go out and buy X, Y, Z and Knuth programming books at £100 a volume"... er... no.).  This is another reason that Newtonian telescopes are good for the amateur - they are simple to make and therefore usually quite cheap.

So we buy a cheap model.  Obviously, cheap is only a relative term compared to your income, and maybe you have no choice but to snap something up on eBay or go hunting through boot sales for children's telescopes.  So what?  That's how you start, and then you can get more stuff as you are able to and as you see a need.  Why splash out money on a hobby that you may not even like?  Would you really notice the difference between a £1000 telescope and a £1100 model?  Not as an amateur - hell, you might not even be able to set them up at all, so why worry about it?

In my case, my telescope was bought for me.  I wouldn't describe it as "cheap", but it's certainly a lot cheaper than anything you'll find in the back of a amateur astronomy magazine.  However, as it turns out, it was quite a good model for the price and certainly more than good enough to start off on.  Hell, it was a lot better than I was expecting.

The criteria for buying a telescope, as described above, are a little counter-intuitive.  You need a large aperture (hole at the top of the tube).  You also need a good focal length (distance that the light bounces after it's hit the back mirror).  I was given a Celestron Astromaster 76EQ.  You can Google the model if you like, and you'll find it's from Celestron (who, with Meade, are the two of the biggest telescope manufacturers, both amateur and professional) and has a 76mm aperture, and a 700mm focal length.  Some clever mathematics (of which you can find calculators online) will tell you that this model allows you to magnify an image UP TO 180 times.  But this is NOT that important.  What's important is that it has a wide-enough aperture to gather quite a but of light, and a long enough focal length in relation to that to get SOME magnification out of it.  But the thing that makes the biggest difference?  It's a Newtonian reflector, and is made properly with half-decent materials and "good optics" (i.e. accurate, clean mirrors etc.).  A cheap telescope that comes with a "200x" lens can't match the light-gathering and detail-gathering power of a decent telescope without proper magnification.  It's like saying that a crane can lift 200x its own weight.  If it weighs nothing, that's not hard, but it might still be useless as a crane.  Whereas a big, heavy professional crane that can only lift twice its own weight is much more useful and can probably lift much more!

And the other factor is that 180x magnification is going to be a very rare occurrence on such a telescope.  You'll rarely be using it at the "top-end" of the scale, and that's the place that's worst for distortion, brightness and other problems.  Not to mention, the chances of anything being clear enough will outweigh the expense of going "higher".  For instance, stars at 180x will look pretty much like they do at any other magnification - they are just that far away.  Planets may occupy more of your sight but they will be more blurry, etc.  The magnification, in itself, is only one particular number that does not mean much if everything else on the telescope is cheap.  So don't get drawn in by the magnification so much as the aperture and focal length themselves.

But the raw specifications of your telescope are not the only things to take into account.  You will need some eyepieces.  These are, basically, lenses.  Yes, we were saying that lenses were "bad" but that's not quite the truth of the matter for everything.  Eyepieces are small lenses that fit on the side of the telescope (in what is called the "focuser", basically the exit for the light to reach your eye).  Different eyepieces allow you to vary the magnification of your telescope without having to move the mirrors or make it longer.  You can't really make a telescope that's so adjustable AND accurate that you could do that without using lenses at some point, so we put the lenses into the "final stage" of the telescope and use them to adjust things to your eye and your preference at the last minute.  This way, the telescope can be built, quite simply, to shove as much light as possible down into the focuser and you can choose whether to see the whole image, or just a fraction of it much "closer up".  And yes, the choice of eyepiece affects magnification but again you can't perform wonders by having a high-magnification eyepiece in a rubbish telescope.

Eyepieces, also, come in a huge variety of styles, designs, and price ranges.  Some of them distort the image, some of them don't, some of them cost lots to make, some of them don't, some of them even flip the image upside-down and others don't.  In general, the most "general purpose" of eyepieces is called a Plössl lens, after the person that invented it.  This is a particular design of eyepiece that gives you not-much-distortion and not-much-light-loss for not-much-cost.  Lenses distort even when they are only in an eyepiece and not magnifying very much, so the design of an eyepiece can make a big difference to how it works for you.

However, it's not as simple as rushing out and buying one eyepiece.  The point of the eyepiece is that it's a small, interchangeable part that wildly changes the way the telescope shows you images for different purposes.  There's no point "zooming in" on a star that's billions of miles away.  It won't get much bigger in your eye, and it probably will just distort before you see any more detail.  Additionally, there's no point looking down a telescope and seeing the same as you could see if you just looked up.  So a variety of eyepieces suit different occasions and different objects being viewed.

Generally, if you buy a complete telescope setup, you'll get an eyepiece or two thrown in.  All well and good, just don't forget that there's more to a telescope than just what the tube can do, and more to eyepieces than just being stuck with the one view forever.  So, having a couple of eyepieces is perfectly sufficient.  Hell, on your first sojourn into space, just the one eyepiece will probably be absolutely fine.  If we buy more, though, or have the option of "one thrown in", what do we choose?

First, there are a huge number of practical considerations.  Does the eyepiece fit in your telescope's focuser?  If not, then you're wasting your money!  Most affordable telescopes will use eyepieces that are 1.25 inches in diameter.  Some really cheap ones will have some weird, odd size just to make you buy their eyepieces, no doubt.  Larger and more expensive scopes might have a 2 inch eyepiece.  And some eyepieces might be the right size width-ways, but be too long for your focuser at all and "dig into" the internals of the telescope.  You can get adaptors and extenders either way, but what will that cost you and will they complicate things too much?  

Apart from that, is the eyepiece comfortable to use?  Eyepieces are used to make the image that's been squished through your telescope aperture into the right size on the back of your eye.  As such, they vary in quite where they assume the back of your eye to be (the so-called "eye relief" of an eyepiece).  If you have to have your eyeball rubbing on the lens for it to work, that's not comfortable.  Similarly, if you have to be standing on the other side of the room to see the image, that's probably not practical either.  So eye relief is a nice simple statistic that the manufacturers will give you about their eyepieces.  The best way to tell?  Try the eyepiece out, even if it's just in a shop, held to your eye, looking at a light on the ceiling.  You will get the best idea of their comfort by using them, and everyone is different.

Generally, though, a basic kit of cheap eyepieces from the telescope manufacturer will be available and recommended in the associated literature.  For a beginner, you can't really go wrong with those kinds of deals.  They will include eyepieces of various magnification, suited to the telescope you have, and be good, cheap all-rounders in general.  They will also choose a variety of eyepiece "sizes" for you.  Confusingly for beginners, eyepieces aren't measured by their magnification (as stated above, that depends on your telescope length too), they are measured in the focal length of the eyepiece.  This is usually stated in millimetres, such as a "20mm eyepiece" (and, yes, astronomy is yet-another-area that often mixes imperial and metric measurements - people will tell you that they have a 4-inch telescope with a 1000mm focal length!).

Also be aware that this "focal length" of an eyepiece isn't related to the actual diameter of the eyepiece (i.e. whether it will fit in your telescope, i.e. 1.25" or 2") or its physical length (whether it'll stick out of our telescope or poke into it), nor to the eye relief (whether it will put the image on the back of your eye properly).  It's merely a statement of the distance that the eyepiece can focus to.  20mm may not sound like a lot, but it doesn't have to be a lot - the telescope has already done most of the hard work and this is the "final tweak" to put the image into your eye.  The way to think of eyepiece measurements is as a ratio, related to the focal length of your telescope (the distance the light bounces around inside it before it leaves the telescope).  A 20mm eyepiece will magnify the image twice as much as a 40mm eyepiece.  Similarly a 10mm one will magnify the image twice as much as a 20mm one.  But a 10mm in a long telescope will be as good as a 20mm in a shorter telescope.   The final magnification, again, can be calculated by various online calculators for you given the focal length of the eyepiece and the vital statistics of your telescope - but note that you can't exceed a certain maximum magnification of your telescope without introducing so much distortion that it's useless. You'll also see that, before you get too stupid on the magnification, the "size" of the eyepiece gets ridiculously tiny to manufacture very quickly. 

Some telescope eyepieces can start at tiny lengths such as 4mm or 6mm and go up to maybe 30 or 40mm.   Generally, if you're on a budget, you can't go wrong with one eyepiece from 1/3rds and one from 2/3rd along the length of that scale.   Starter kits normally include a 10mm and a 20mm lens to cover most of the basics, for instance.  If you later become frustrated by the lack of magnification, you can always buy eyepieces of other sizes later and some very expensive eyepieces will allow you to have a "zoom" eyepiece, like a zoom lens on a camera, that can operate at any focal length in their range (e.g. 8 - 38mm, for example).

So, you've bought (or your telescope came with) your 1.25", 20mm, good-eye-relief, Plossl eyepiece and it fits into your telescope.  Perfect.  We're almost ready.

There is just one minor factor to bring in at this point.  How the hell are you going to hold the damn thing?  The answer, almost universally, is "don't".  Actually holding or touching the telescope is, as you will find out, quite useless.  Not because you're not strong, and not because they can't make small telescopes.  When you are looking for a tiny dot in the sky at 200x magnification, you won't be able to keep it still enough to see anything.  I guarantee you.  Why?  Because if you have movement in your body that's even 1mm, you're suddenly seeing that as a 200mm movement through the telescope (and how big is your eye?).  The tiny little touch of a dial while you are viewing will look like someone's kicked your telescope down a set of stairs while you're holding it.  It's just not possible, as a human, to hold it still enough.

This is why people invented tripods.  Put the telescope on a tripod and no movement, no problem.  Generally this is true.  You can quite happily attach a telescope to, say, a video camera tripod and get some good viewing if you want.  It's certainly an option for those home-made people among you.  But the problem there is that the telescope is designed to look up, not along.  By the time you attach it all in the right way, looking up at the sky, you'll quickly realise how unsuited to the task a basic tripod can be.  That's why some clever people invented telescope mounts.

Mounts come in two basic types.  They are nothing more than a way to put a telescope on a tripod such that it's more comfortable to use.  While there, though, they have to do lots of things that a tripod alone cannot do.  The first is to make it convenient to look up at the sky rather than along at the ground.  That's quite easy.  The next is to make it so that the telescope can be moved around the sky.  So telescope mounts have adjusters and little handles and wheels you can use to move the telescope around.  You might think that this is just so you can move between objects in the sky and not have to unscrew things.  You'd be wrong.  The biggest problem with the night sky is that it never stays still.  It might look like it, from a distance, but it's always moving.  You know that the Sun goes up and down and from East to West, but so does EVERYTHING else.  The reason the Sun comes up is not because the Sun is moving, or because the Earth is moving around it (both of which are true, but not the "biggest" movement up there).  It's mainly because the Earth is spinning, like a spinning top.  As the Earth spins around, the stars appear to move the opposite way (like when you're in a car and it looks like the other cars are moving backwards when you overtake them).

How fast does it move?  It depends on what you are looking at, and how you're looking at it.  The sun, for instance, moves pretty fast - it can be in and out of sight in half-a-day.  As does the Moon.  The planets are not slow, but slower.  And generally the field of everything else star-like out there moves at the slowest pace.  Pretty much nothing at all stays still in the sky, except for artificial satellites (those in "geostationary orbit", like the ones that power your satellite TV or the GPS network) and it's extremely tricky to see those anyway.  Not only that, they don't move just move but also appear to rotate as they cross the sky.  If you were to "draw a vertical line" on the sun in the morning dawn, it wouldn't be vertical by the evening sunset.

But is this movement a problem?  Well, yes.  Because if you're looking through a 200x magnified image, then the sky appears to move 200x as fast.  So what is a tiny, unnoticeable, graceful slide across the sky when you're on the ground, is more like chasing a fly around a room when you are looking for smaller objects through the telescope.  At even a modest 70x magnification (enough to see almost all of the Moon in your eye and nothing else), the Moon will be out of your view in only a matter of two minutes or so.  It will literally slip across your image that quickly.

No problem, though, because our mount has adjusters and wheels to counter that, right?  Correct.  However, if you do any amount of astronomy you'll quickly tire of wheeling your view around the sky to keep track of a tiny dot of a star, only to lose it because you accidentally tapped the side of the telescope while fumbling for a wheel and knocked it out of view and have to go find it again.  And you might have to think about the rotation too, and adjust for that.  So what's the solution?  There are special types of mounts.  The basic, "obvious" kind of mount is like a video camera tripod mount.  You can turn the telescope/camera around to point in any direction, and you can move it up and down to look up and down.  This is called an Alt-Alzimuth mount (Altitude is the up/down, Azimuth is the North/South/East/West of it all).  This, believe it or not, is a pain in the backside to view things that are moving across the sky if you're controlling it manually.

The stars don't move like that.  Like the Sun, they come up from the horizon, curve across the sky, go over our heads, then come back down.  And if you're on the equator, it goes DIRECTLY over your head, but if you are more North / South, the Sun goes more South/North instead.  Also, it rotates as it does so.  It's a very complex path that the Sun traces in the sky.  And unfortunately, stars move in the same way because they move for the same reason (the Earth spinning).  The solution is what's called an Equatorial mount.  This looks almost the same as an Alt-Alzimuth mount, from a distance, but it has some weird angles, extra dials and the telescope "moves funny" when you turn one of the wheels.  It's specifically designed to do nothing more than compensate for the Earth's spin.  It has two main adjustments you can make (called Right Ascension and Declination), both of which appear to move the telescope at an odd angle (i.e. not in a straight line up or sideways, it's more like they "criss-cross" the sky).  It also has an extra setting so that you can tell it where on the planet you are - specifically what your latitude is (i.e. how far away from the equator you are).  There's no complicated electronics, it's all just cleverly shaped gears and, when you have one, it makes your life easier.  You have to learn how to use it, but it means that you can follow a star or planet perfectly just by slowly turning only one adjuster.  In fact, it's SO easy to keep things in view once you have one, you can buy a little motor that also has no electronics on it and does nothing but turn the adjuster for you at the right speed (it's literally but a 9v battery and a geared motor in some models) and you can keep a star in your view all night without touching the telescope.

But let's get back to the question of buying.  Which mount should you have?  Alt-Alzimuth mounts are intuitive and easy to understand, but a pain when you want to follow a particular object.  Equatorials need a bit of a setup (called polar alignment, to make sure they are facing North when you start), but can save you a lot of work when following.  Either can be "misused", allowing you to just sit and manually keep the image in the eyepiece yourself without any fancy setup.  Which one you choose is a toss-up of cost and effort, and for your first telescope it barely matters.  Most telescopes will come with Equatorial mounts, but not all.  Cheaper telescopes are likely to come with the simple Alt-Azimuth mount.  And there are a special category of telescopes (called "Go To" telescopes), which are all computer-controlled and make the whole question moot as you'll never move the telescope yourself and the computer will do all the hard work no matter what kind of gearing you have on the mount.  As stated earlier, I'm totally ignoring that last category.  That's just cheating!

This all sounds like a lot of equipment now.  Telescope, eyepieces, tripods, mounts.  It sounds a lot, but it's not.  The telescope I was given came as a set of all of the above (as do most amateur telescopes).  The Celestron Astromaster 76EQ came with a tripod, equatorial mount, the telescope itself, a 10mm and a 20mm eyepiece.  And it could cost less than £100 if you look around enough and don't just buy it off-the-shelf.  I consider that acceptable for someone entering a new hobby, but of course I didn't pay for my telescope and your opinion may differ.  There are cheaper ones and much more expensive ones, so you can shop around now that you know roughly what you're looking for.

But what do we get for that price?  I don't mean "what's in the box?", I mean what can we actually do?  It depends on exactly what you've bought, but even if you're in the realm of "children's starter" kits, you should at least be able to see the Moon, including individual craters.  You may say "Wow, why would I do that?" but the fact is that they can be breathtaking.  Look at the ones on the EDGE of the darkness of the Moon, and you'll see shadows which help to pick out the individual craters.  You can see some quite amazing detail that you wouldn't get by looking up.  And, despite what you might think, seeing it for yourself, under your control, where YOU choose to look makes it look more "real" than anything NASA might post on their website.  It's like being a driver or being a passenger - both see quite different things depending on where they look and as a driver, you are much less likely to experience motion sickness because you're CONTROLLING the car yourself.  Getting a Moon crater into your eyepiece yourself is the same kind of experience and everything looks more "3D", if you like, because you are running your eye over a real 3D object, not a flat 2D photograph of it.

What you WON'T see, with any telescope?  You won't see anything to do with the Moon landings.  Sorry, you just won't, without spending an INCREDIBLE amount of money.  It's not that there's nothing there to see, but just that it's all so tiny in comparison that it's incredibly hard to see.  NASA can barely pick up images of the previous landing sites and the equipment left there, themselves.  It's just that tricky.  It's like taking a photo of the whole Earth (seeing the whole Moon at once is pretty easy with any amateur telescope) and finding YOU, specifically you, on it.  If you've seen Google Earth (not the StreetView, which was taken with cameras driving on the road, but the overhead satellite view), you'll see what I mean.  Even cars come out as blobs of colour and most of that imagery came from airplanes.  The furthest out imagery probably came from satellites orbiting the Earth and you can barely spot roads at all, let alone houses or cars or people.  The Moon, by comparison, is about 10 ten times further away than any man-made satellite we have.  So, going the other way (looking at the Moon from the Earth), even with a telescope, is like looking at the most zoomed-out Google Earth satellite image from the other side of the room.  You'll be lucky to see anything that is smaller than a mountain.  Even the best telescopes in the world, which can be the size of entire factories, joining together and working together to make an image couldn't pick out a decent image of the lunar rover, or Neil Armstrong's footprint.  So don't try for that, try to find something else wondrous instead.

With any decent amateur setup (and, again, by decent I mean "not a toy", and not "costs hundreds of pounds"), you should indeed be able to see the planets.  Hell, I saw one with the naked eye, so I'm sure you can do better through a telescope.  How will they appear?  You will not get the prevalent NASA images of fine details and individual craters.  Planets are about 1000 times again further away than the Moon.  With my Celestron, I can get the brightest planets to resolve to quite obvious planet-looking things.  I can see the spherical shape.  I can see the rings on Saturn.  I can even see the stripes of clouds in the atmosphere of Jupiter.  If I really "zoom in" as much as possible, I can get some more details of the atmosphere, but that's about it.  With bigger telescopes and other techniques, you can get better images that show more planetary details, but remember, you're accustomed to NASA images taken with HUGE telescopes, sometimes thousands of miles up in space, that cost billions of pounds to put there.  You won't get that.  But that doesn't mean that what you do get can't be fabulous, and in fact the planets are one of the best targets for other astronomy techniques or upgraded equipment.

What about the stars, though?  Sorry to say it, but I've discovered that most stars are just stars.  You zoom in, it's still a star, a tiny dot a long way away.  If you're lucky maybe it's two stars close-up that look like one in the sky.  They aren't that interesting.  The constellations?  There's nothing to even "see" there, it's just a particular pattern of stars.  Nebulae?  Ah, now we have more interesting depths to delve before we can get there but yes, in theory, if you're prepared to work at it.

What affects most of what you see?  Like my initial discovery of Venus:  Where you are on the planet, and sheer luck.  Weather is actually your greatest enemy.  Even a thin, misty cloud can ruin your observations through the best of telescopes.  Most large observatories are on the tops of mountains, above the clouds, for exactly this reason.  Waiting for a clear night is probably the worst part of being an amateur astronomer, especially if you've just bought some new equipment and are desperate to try it out.

Your next problem - like my day-to-day experience of astronomy - is cities and bulbs.  Believe it or not, the light you are trying to gather from remote planets and stars is so weak by the time it gets to Earth that even the lowliest light will wash it out to the point that it's invisible.  In fact, stray light is such an enemy of the astronomer that it causes all kinds of problems.  Your "night-vision", which is the part of your vision best able to see in the dark, only comes about after you have spent several minutes in darkness.  This sensitivity is required if you want to see faint objects at all, or bright objects clearly, even through the best telescope.  That's just how weak the light you're looking at can be after travelling millions of miles.

As such, living even NEAR a city can drastically affect what you see in the sky.  Streetlights, houselights, stadiums, are all just throwing light upwards (that is also, incidentally, a complete waste of energy) as well as on whatever they are supposed to be lighting.  This generates a huge "beacon" of light in any city that's near you, which can wash out the sky.  It's not that the stars aren't there, it's that you can't see them through all the bright light of the city (like trying to see a speck of light in a brightly-lit room).  It's not unusual for cities to also have a certain atmosphere over them as well (e.g. smog, fog, heat-waves, etc.), which reflects this light and makes the problem worse.

But it's not just huge cities that can be a problem.  Your own houselights are closer and more blinding to you. Just walking into the house to check what eyepiece you've picked up in the dark will ruin your night-vision as the light-sensitive parts of your eye recoil and hide themselves, and it will take a few minutes in the darkness before they think it's safe to come back out.  Even a small torch will do the same, and you'll find that what you could see in the telescope before you turned the torch on (even facing away from you) won't be visible for a few minutes after you've turned it off.  Most astronomers counter this - of course you can't sit in the complete darkness for ever and ever, stumbling over your telescope every time you move.  The general solution is to use low-level red light, rather than white.  This affects your night vision much less, so it's a common sight to see red-filters on illumination sources, or even just "only red" bulbs in specialised astronomical torches.  Shining a white torchlight around at an astronomer's convention will probably get you thrown out...

But even in a city, you can still get some good viewing.  I observe from a back garden, in the middle of a major city, with trees and houses obscuring vast portions of my view, and still get good viewing when the weather is clear.  In fact, the weather is the most major impediment, not anything else.  So, what's the WORST you can do, with a under-£100 telescope, in the middle of a city, on an average night, as a complete amateur that doesn't know what they are doing, what can you expect to get?  Well, I can take photographs through my telescope - which I'll talk about later - but they really don't do justice to what you can see through the eyepiece yourself (the difference between actually seeing your friend, and looking at a photo of them).  So I've chosen a handful of my absolute WORST photographs.  This is what I get:

 

My first ever recorded image through a telescope - Jupiter, with the atmospheric "stripes" clearly visible.

 

A few tries later, on a VERY bad day for observing, with all sorts of problems caused by everything from the weather to trees in the way, to things falling off the telescope, to it starting to get cold and me wanting to go indoors.  This is Saturn, with it's rings.

 

And the bog-standard, easy-to-do Moon.

Note that these pictures are basically what is left if I take EVERY photo that I've ever managed to take through my telescope, removed all the ones that are just blobs (where I haven't focused anything at all), blurs (where I've kicked the tripod or moved the telescope somehow), accidents, entirely-black, etc. and then I take the simplest, most terrible example of each of the above objects (which was usually just a test image, not an actual image I was intending to keep).  So this is pretty much the worst you can get, from the above telescope, without really trying.  And, to be honest, two of those photos were taken by quite literally just pointing a camera down the eyepiece of a telescope which is one of the worst ways of trying to record an image through a telescope.

This is pretty much the MINIMUM you can expect in a worst-case scenario, in a terrible location, from a pathetic amateur, from a under-£100 telescope, and even these don't do justice to what you can see through the scope yourself (my photographic skill is precisely zip!).  When I found this out, I was quite surprised, I thought it would be much worse.

How did I get those images?  Well, my initial tinkering with the scope was enough to show me things much better than the above.  You can see much more with the eye than you can with a photograph.  Most of it was the initial learning experience but I was still quite happy with what I got from it, and it was enough that I did look through the telescope accessory catalogues and identify the kind of problems I was having and how to fix them.  Mostly, these problems were practical.  Mainly, I wanted to get some photographs of what I was seeing and already had a consumer-level digital SLR camera available to me, though I don't doubt for a second that someone willing to try couldn't get better results with even an ordinary digital camera nowadays.  I know I would have tried it if I didn't have an SLR available, but that was just misinformation on my part from what I've seen - cameras even on mobile phones can take some fantastic images with the resolutions they have now, if you're prepared to spend the time to try it.

Once that decision was made, the rest was just reading up on the Internet for what I would need to do that.  There are a myriad ways to get an image from a telescope and into a camera.  The simplest (which is how the above were made) is to literally just point the camera at the eyepiece once you are all lined up.  You might have to disable autofocus (because it's NOT focusing on the eyepiece at all, but just beyond it) but that's no hardship on any modern camera.  You aim the telescope, get a good view, then just put the camera where your eye was and press the shutter.  You can play with the camera settings but for anything sufficiently bright (like the Moon), you probably won't even need to do that.  And the hardest part is just holding it still in the right place for the image to be sharp, not blurry.  Some "astrophotographers" even use a second tripod just to hold the camera still.

I wasn't happy with this, though.  I got some images, like the above, and they got some "likes" on my Facebook from my friends but I wanted to show what I could see when I looked down the telescope myself, and that had a lot more detail to it.  There are a variety of ways to improve on this, the simplest of which - if you have a good camera - is to actually join the camera direct to the telescope without any eyepieces in between.  Most cheap cameras have a built-in lens that you can't change.  So to join the camera to the telescope is just a matter of finding a physical adaptor that holds it in place, near the hole for the eyepiece.  Those exist and are quite cheap.

If you have a camera with a removable lens, though, like most digital SLR cameras, why would you want more glass in the way of your image, and why would you need a terrestrial lens to do anything?  The telescope itself is basically a HUGE lens that can be adjusted in a myriad ways to suit (you can try it in daytime if you like - it's quite easy to use the telescope as a huge zoom lens and I can see several miles away, or the moss growing on the chimney of a house down the road).  So why not just join the camera "body" (without the lens) direct to the telescope?  That's exactly what you can do.  In this case, I had a Canon camera and there is an established standard for connecting photographic equipment to things like telescopes, called a T-Ring.  One "Canon T-Ring" (to join the camera to a standard ring)  and a "T-ring eyepiece" adaptor (to join the telescope to a standard ring) purchase on Amazon later , and I was able to literally screw the camera directly onto the telescope focuser (the bit that the eyepieces go into).

This brings about a number of problems, some of which aren't obvious.  Firstly, with the camera in the hole that you would look through, you can't see a damn thing yourself.  Some cameras have a "Live View"-type mode, where you can see what the camera sees on a screen on the back of the camera.  This helps but beware - that screen is NOWHERE NEAR as good as your eye, and it can even knock-out your night vision!  It's not unusual to get to a point where you can see something with your eye through the telescope that is invisible on that screen.  The solution, really, is to remove the camera and only put it in there once you're lined up with your object by eye.  This is a bit of a pain (especially as changing the eyepiece for the camera can be fiddly and can knock the telescope), but about the only way to do things if you don't have Live View or can't see what you want on the Live View.

The next problem is focus.  We spend money on a telescope so that a huge portion of the light from a very distant object can be "focused" onto a small area at the back of our eyes.  The various mirrors and lenses do this for us.  However, in a camera, the "focal point" might not be anywhere near where your eye would be, when looking through the same equipment.  In fact, this is why cameras have their OWN lenses, to modify where the focal point falls.  But we just disconnected all of those lenses.  Now, telescopes have a "focuser", this is a little sliding arrangement on the part that holds the eyepieces and allows you to move them back and forth until you can get the image to land on the focal point of your eye / camera.  This is usually fine and works wonderfully.

The problem comes from some cameras which have a rather "deep" focal point in them, and some focusers that can't adjust enough to compensate.  So, as it turns out, my purchase of a cheap, physical T-Adaptor actually didn't help me at all.  All I could get was out-of-focus images because the focuser couldn't move enough to put the image onto the right part of the camera.  This is a pretty common problem, it has to be said.  Not all telescopes have been designed with this in mind, so not all of them can do it on their own.  You might be lucky, but bear it in mind, and test first if you want to follow this path - you need to see where the focal point on your camera needs to be, and where your telescope / focuser can put that focal point.

There's a simple fix, however, but it depends on your telescope and adaptors.  Some T-Adaptors will let you put an eyepiece INSIDE them, so you can just use the same eyepiece as you normally would to bring the focus closer.  But this very much depends on the eyepieces you have and the distance it needs to move the focus.  For some, this is the only solution required (which is why T-Adaptors like that exist - for some, they are all you need).

But if we can't get the light to focus without any lenses, or with only the eyepiece, then maybe we can find another lens to help.  There's a particular type of lens called a "Barlow" lens which is often used to solve this problem, also named after its inventor.  A Barlow lens is one that goes on the end of another eyepiece, and you can effectively think of it as a "doubling lens".  Whatever you attach the Barlow lens to will be twice as magnified as without it.  A nice side-effect of this is that it can also increase the focal length of the eyepiece so that it CAN reach further out of the telescope and into your camera properly.  And, fortunately, because of the design of it you can often get Barlow's that are integrated with T-adaptors, or can attach to an ordinary T-adaptor.  If I'd known that, I wouldn't have bought the above, non-Barlow, adaptor!

So we put the magical Barlow lens in front of the camera instead, join it all together with T-rings, and now we can focus images for the camera properly and it's all conjoined into a single unit with the telescope.  This might not have been necessary at all with some cameras or some telescopes, but if you have the same problem, you now know what can be done.

These Barlow's, however, sound useful without a camera.  Can't we just put them in front of any eyepiece and "double" it's magnifying power?  Yes.  You can.  That's precisely what they are originally intended to do.  An 8mm eyepiece in a 2x Barlow gives roughly the same image as a 4mm eyepiece.  Again, there is a cost in terms of quality, distortion and "field-of-view" (how wide an area of space you can see through them) but this is a perfectly viable setup in terms of an amateur astronomer "doubling" the number of eyepieces available to themselves.  Buy 2 eyepieces, and a Barlow, and you effectively have four combinations.

But what if we put a Barlow in front of a Barlow in front of a Barlow in front of a Barlow?  We could work magic!  The quality would deteriorate and the distortion increase to the point of uselessness around the second Barlow.  All lenses distort the image - that's their job - and magnifying a distorted image will distort it even more.  This is why you shouldn't think that magnification of anything will "work magic" with any piece of your "optics".

If you shop around on the Internet, you can even find "5x" Barlow's that claim to increase the magnification of your eyepieces by five times instead of just two.  There's a reason that these are so cheap and you won't find them in serious astronomy shops.  Magnification is NOT the be-all-and-end-all of a telescope, quality is, and anything past a 2x Barlow is introducing so much glass and thus distortion into the light path that you probably won't be happy with the result.

Before I'd even got this far, though, I'd noticed that the eyepieces I had were fine, but I thought the view was a little too "zoomed out".  I could fit the whole Moon on a single image, for instance.  I invested in a little kit of extra eyepieces - and fortunately the Celestron kit that I bought for the additional eyepieces came with a 2x Barlow in it.  Notice that it's only a 2x Barlow, not out of cheapness, because because there's no need for anything greater if you have a nice set of eyepieces, and you're better off buying the other eyepieces and having less glass in the telescope than relying on the Barlow to do everything and work wonders.  In fact, anything past a 2x Barlow seems to have a reputation among astronomers that basically makes them laugh at you for buying it, unless it's an INCREDIBLY expensive and serious piece of kit on an already high-end telescope.

So what would we look at, and how would we find it in the sky?  Well, here I must advocate a little bit of cheating for the beginner.  I wouldn't go so far as a "GoTo" telescope, but it's certainly nice - at first - to have some tool to help you.  If you pick up an astronomy book or magazine, they will usually include star charts that you can use to orient yourself.  You should be able to look up in the sky and spot a couple of the constellations just about anywhere on a clear night, but this isn't always guaranteed in urban areas.  And although you can probably find your way from the Plough (Ursa Major, which most people should recognise) to the "smaller Plough" (Ursa Minor), and from there your astronomy book will invariably point you towards the North Star (Polaris) or Cassiopeia, I don't get much excitement out of those objects themselves.  All the interesting stuff is NOT on the constellations.  They may be near, inside or around them, but that's because there's a constellation in every part of the sky.

And as the sky rotates around you, the stars stay pretty fixed relative to each other.  Ursa Minor will look like Ursa Minor all the time for at least the next few thousand years, and will be in the same part of the sky relative to the other constellations (which is why it's used as a guide to orienting yourself to find Polaris, etc.).  Therefore, they are very useful guidepoints, a nice backdrop that we can use to orient ourselves in the sky, but they aren't particularly fascinating in themselves (there are exceptions, obviously, but they aren't the kind of things that you can look at first as an amateur).

But the planets are, although predictable, pretty random to the human eye.  Sometimes they will be visible in your part of the world, sometimes not, sometimes they'll be higher, sometimes lower, sometimes more East, sometimes more West, sometimes faint, sometimes bright, sometimes behind other objects, sometimes out in the open and sometimes even appearing to stop and move backwards.  Predicting them on paper is, obviously, possible - even the ancients were able to predict their appearance and location - and while I think it's not beyond an amateur to orient a telescope and point it at a certain location themselves, finding the location that you need to point to is something that I "cheat" on.  Especially when I was beginning, the procedure for aligning an Equatorial mount to the North can take most of the evening unless you happen to have a nice mount and clear skies and know what you're doing already.  But my viewing area is primarily to the South, and trying to orient it against other things, that you can barely see, was a pain.

Even when just aligning the telescope could take me all night, and constellations are barely visible, I wouldn't go to the point of having the telescope do all the work for me, but I prefer to use starcharts or software to find the objects I want to look at.  A starchart is pretty obviously just a map of the stars, and if you have access to up-to-date ones, e.g. from a monthly astronomy magazine or some such, then you can use them just as you would a map.  Find a star/constellation that you recognise in the sky, work out where your target is relative to that, and adjust as necessary.  It's quite common for beginners to memorise how to "hop" from one constellation to the next so they can navigate the whole of the sky and spot constellations whose shape they otherwise wouldn't spot in the sky.  Personally, in a big city, you can have a hard time even seeing the constellations, and looking through the telescope, it's quite hard to recognise one even if you know what it looks like, so software can provide a better way to get yourself started on an evening of viewing, and confirm that you are looking at what you're supposed to be looking at.  

What kind of software?  There are myriad pieces of astronomical software.  I remember when my brother was studying astrophysics he used something called EZCosmos (back in the days of floppy disks and DOS), and they haven't changed very much since.  My personal preference, though, is always towards tools that people are actively working on to improve, and that are free.  This generally points to "open-source" or "freeware" software (which are two different things, but the explanation is outside the scope of this article).  There's nothing worse than being lumbered with some software tool that cost you £40 to buy and for which you need to pay for updates, or extra bits to go on it, or that doesn't do what you need when a free piece of software does.  And the best thing is that you can point people at the free software, or even give friends a copy of it, and there are no legal problems.

Many telescope kits come with such software, but I often find it inadequate in one way or another.  My Celestron telescope came with a "light edition" of one on CD, which is okay, but doesn't have a lot of the advanced features, and then bugs you to upgrade to the "full" version if you want them.  I just find that annoying, so I sought out an alternative almost immediately.

My personal preference, on PC, is Stellarium (http://www.stellarium.org/).  This is a wonderful (open-source, and thus free) piece of software that incorporates so many useful things for the amateur astronomer that you'll probably never need another.  However, because it requires a PC it can be quite hefty and that might not really be the kind of thing you want to drag around with you on a cold night (with your laptop screen destroying your night vision too!).  So I also make use of some smartphone applications - Google Sky Map (free) and, lately, SkEye (free, with a Pro version that's not much different at all and mainly exists so you can "buy" the application to support the programmer).  Each piece of software has a "night-vision" mode, that you can use the program in an all-red interface, this is never perfect but usually enough to stop you losing your night vision for minutes at a time every time you glance at the screen.  They all have thousands of stars, planets, constellations, nebulae and other objects pre-loaded into them.  They all allow you to look all around the sky and work out what is where at any particular time and location on the Earth.

The smartphone applications, particularly, have one major advantage aside from their portability.  Most smartphones nowadays have GPS built-in and electronic compasses and accelerometers.  If you already have such a smartphone, the right software, combined with such sensors, can make use of everything from the Earth's magnetic field, to the movement of Earth's gravity or the phone itself, and your position on Earth to come up with an astoundingly accurate map of what is immediately in front of the phone, even if you can't see it in the sky.  With both smartphone products, for example, you can hold your phone at arm's length and sweep it slowly around the sky and it will draw on the screen what stars, planets and other objects are hidden behind the phone screen.  It's like a little pair of X-ray specs looking through the sky and showing you all the interesting things behind your hand.  As such, it's wonderful for recognising the constellations, seeing exactly where Jupiter is at the moment, whether that really is Polaris you're looking at, and a myriad other possibilities.

Although PC software like Stellarium can do the same kinds of job, because they are running on a bulky PC or laptop without such gadgets as a magnetic field sensors, they are more usually useful as an "offline" kind of tool.  You can use them in the field, and many do, but it's more likely that you'll use them to check where Jupiter is ("Oh, right, it's just to the right of Spica at the moment"), and then go out and find it.  This isn't a bad thing at all, and I highly recommend that you try this first.  The smartphone apps, however, can be very useful for confirming that what you see in the sky is Spica, or Jupiter, Ursa Minor, or whatever else you want to look at, especially if the viewing is particularly poor.  I don't regard the smartphone functionality as vital, but it can be useful, but in general an astronomical software on PC or smartphone, or at the very least an up-to-date starchart (which is what the software mainly is), is pretty vital for the amateur.

The other wonderful thing about both types of software is that you can also "fast-forward" or even "rewind" time.  This is extremely useful in both directions - this is how I confirmed that my surprise planet was Venus, by going back to the previous evening on the smartphone apps and seeing what was in the North, near the Moon on that night.  And if the weather forecast is favourable tonight, or I have a day off next week, I can fast-forward time on the app and see what planets should be visible from my location at that time.  Is it worth staying up late for Saturn, for instance, or does it not rise above the horizon until 4am?

SkEye also has another feature called "PushTo" location.  With "GoTo" mounts, you tell it what you want to see and it automatically aligns the telescope, finds the object, wheels off and points you directly at it.  With PushTo, it's a kind of very simplified GoTo.  You can tell it what you want to see and it will give you a rough direction that YOU move the telescope to.  If you strap the phone to the telescope it can even be almost as good as a GoTo telescope, but it also works just in your hand ("oh, I see, it's more to the right, and up a bit, and over there, right, I'll just move the telescope"). It's a small difference, but a critical one, because it can make you use your knowledge of the night sky to work out where you have to go, and get used to the operation of the telescope.  After a while, you might even find yourself using it less: "Oh, right, Jupiter's just below Spica at the moment", and then off you go yourself without any extra help.

And the software I've specified is some software that should stay with you for a long time.  Stellarium, in particular, is able to even connect to GoTo mounts and orient you automatically, and do any number of clever things that you might want to do.  It's not the kind of software you'll outgrow as a keen amateur, and useful even for a casual "one-off" verification of the night-sky.

And now, we have an image, we can focus it into our camera, we know what to point out, we can just get clicking?  Well, not quite.  You'll get nice images but learning about your camera (outside the scope of this particular article) will work more wonders.  ISO modes (sensitivity of the camera to light), exposure times (the time you leave the camera shutter open when taking a picture), all sorts of other factors come into play and can make a visible image in the eyepiece become anything from blazingly bright light that washes out the whole image, to a completely black image.  It's all a question of adjusting for your purpose and the image you want to take, like any photography.

The next biggest problem of imaging is one of speed.  Things move fast in the sky, even if you can't see it (but the whole universe flips round every 24 hours, if you think about it from an Earth point of view).  The amount of time that your camera takes to capture an image is related to how bright it is.  And astronomical objects are quite faint.  So you have to have the camera open its shutter for quite a while to get a nice image, so that the light has time to "build up" on the camera sensor / film (and, yes, some astrophotographers still use film).  A brief flash isn't enough to get the faintest stars or detail on the planets, so you have to let the image linger on the camera.  30-second or longer exposures are not unusual for some purposes.  And while everything is moving, that's a huge challenge to keep everything still (or, more accurately, move everything at the same speed) for that amount of time.

But we have our equatorial mount!  Yes, and we need to keep adjusting it to keep the image centred all the time.  If we don't, the camera will just blur all the movement together.  And the biggest problem isn't really keeping Jupiter in the centre frame (challenging though that can be) - you can do that quite well once you've had a few goes if you have any patience and a steady hand.  The problem is simply the taking of the photograph in the first place.  What do you need to do to take a photograph?  Press a button.  Where is the button?  On the camera.  What's the camera connected to?  The telescope.  How much do you need to move the button to activate it?  Several millimetres.  What does that look like through the camera lens and all that magnification?  Like someone slapped your camera hard while you were taking the photograph.

A remote control, as daft as it sounds, is one of the best things to have for your camera if you're trying to take good photos.  This is why professional photographers have that little "button on a cable" that they use to take photos, and they aren't even magnifying things anywhere near as much.  Other cameras have remote controls like those for your television, or even computer based ones where you can press a button on a laptop and the camera takes the photo.  Basically, anything so that you don't have to touch the camera to take a photo.  Even a self-timer (so that you can press the button, and then the camera can "wobble" for 30 seconds before it actually tries to take the photo) can be of enormous use here.

How big a problem is this wobble?

This is filmed with the camera fully attached to a solid screw-in bracket, locked tight into the eyepiece focuser, on a solid, sturdy tripod, on solid ground, looking at the Moon.  You'll notice firstly how fast the Moon moves (it moves completely across the shot in a matter of minutes), because I wasn't trying to follow it in any way - that's not the camera / telescope moving, that's the Moon.  And, no, the film is not sped up in any way.

You'll also notice that the wobbles are definitely present at the start, and at the 1:00 mark, and towards the end.  What was I doing to make it wobble?  Was I kicking the tripod, playing with the camera?  No.  The wobbles are TINY, gentle adjustments to the telescope focuser where I literally touch it as lightly as I can to adjust the focus by a tiny, tiny, amount.  I have no other parts of my body near the telescope, I'm not touching any overhanging part of the arrangement (i.e. when you have the focuser and in that a Barlow and in that an eyepiece and on that a T-adaptor and on that a whole camera, touching any part of that setup is much worse), and nothing is moving at all.  You wouldn't even be able to see movement if you were watching me make that adjustment, but through the eyepiece that kind of wobble can destroy a captured image even with the smallest of exposure / shutter times. That's also at about 75x magnification.  It can get a lot worse when you're not looking at the Moon, but something smaller and further away.

Hopefully, that should all be enough to get you started in astronomy, with the correct expectation, knowing what to buy, and roughly how to do most things.  

With Stellarium, a £100 scope set, and a clear night, you can get started quite comfortably with astronomy.