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I have always been interested in space and astronomy (in my youth - I wanted to be an astronaut).

However for various reasons, I never quite got started. I now want to get started - small but steadily. I live in a city, ergo: light pollution is a problem - however, I would like to get a telescope (maybe a second hand one but a good make), maybe join a local astronomy club ?

In an ideal world, I will get a "good" telescope which has the following attributes

  1. Can be extended to make progressively more powerful
  2. Can use one of the opensource astronomy packages (I am a programmer!)
  3. Allow me to take photographs

Can anyone provide me with a series of steps to help me finally turn my dream of observing the skies into reality?

Note: I am aware that it is very likely that I will have to start with a small, hand held telescope - but I like the idea of a telescope that will "grow with me" - if that is at all possible.

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Since you say you're a programmer, I see where criterion #1 comes from. But telescopes are not computers, you can't upgrade the CPU today, the RAM tomorrow, and so on. A scope is defined largely by its aperture (the diameter of the objective lens or mirror). That puts a major cap on pretty much everything else, performance-wise. Aperture is like an old boarding school taskmaster who says "you're allowed up to here, no more", and anything else you may do can only place you lower than that ideal level of performance.

Scopes optimized for visual and scopes optimized for photo are different animals. They are interchangeable to some extent, but after some point their respective traits start acting up. Usually, people start with a small price-efficient visual scope (like a small dobsonian), then migrate to astrophoto after some learning is done. But if you're intent on doing AP directly, fine.

The instrument that's typically used for AP is some kind of catadioptric, like a Schmidt-Cassegrain (SCT), on a tracking mount. It doesn't have to be an SCT, it could be a refractor, a Ritchey-Chretien, it could be a newtonian, or what have you. But an SCT is typically short, stubby, and rather not unwieldy for its aperture, which are good attributes if you put it on a tracking mount.

The mount doesn't necessarily have to be a go-to mount. I would argue that go-to is a waste of money if you're smart enough that you can use a star map (either paper, or software). But it absolutely needs to track the motion of the sky on one axis, because you're going to take a lot of long-exposure photos.

Some examples:

http://www.telescope.com/Telescopes/Astrophotography-Telescopes/pc/1/19.uts?currentIndex=0&pageSize=34&defaultPageSize=20&mode=viewall&categoryId=1&subCategoryId=19&type=thumbnail2level

As you can see, AP scopes and mounts are expensive. You could get away with a mediocre scope, and still take good pictures, but a bad mount is a deal breaker.

A lot of beginners are like "okay, that stuff is way too expensive" and simply purchase a small Cassegrain on a cheap go-to. It's definitely less expensive, but the performance changes accordingly. Some examples:

http://www.telescope.com/Telescopes/Cassegrain-Telescopes/pc/1/14.uts?currentIndex=0&pageSize=51&defaultPageSize=20&mode=viewall&categoryId=1&subCategoryId=14&type=thumbnail2level

Finally, if you decide to take a while and school yourself in purely visual astronomy before purchasing a killer AP rig, you could start with a bang-for-the-buck visual scope such as a classic or Intelliscope dobsonian - as much aperture per coin spent as possible:

http://www.telescope.com/Telescopes/Dobsonian-Telescopes/pc/1/12.uts

(I'm in the US, but the general principles should apply; maybe less so the particular examples above.)

EDIT: Here's a bare bones rig for AP:

http://www.garyseronik.com/?q=node/52

If you have a digital camera already, it will cost you almost nothing, and you could assemble it in one week-end.

Florin Andrei
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Astronomy is really a "knowledge hobby" rather than a "hardware hobby." Understanding what's out there and what's its significance should come first; you can't buy your way in through hardware "toys." Many beginners make the mistake of getting a telescope before they have any idea how to use it: how to actually find things in the sky to look at. So my advice is to go slow, do a lot of reading, join a club, use your eyes first of all, then binoculars, then a telescope, and then, way down the road, think about photography, which is by far the most difficult and expensive part of the hobby.

There is no such thing as a "hand held telescope." Even the lowest power telescope requires a solid mount in order to see anything. The only exception is small binoculars. I generally recommend 7x50 or 10x50 as these are hand holdable, and allow you great freedom in exploring the sky. Since you mention light pollution as a problem, I'd lean towards 10x50s, as these darken the sky background better than 7x50s, and the slightly higher magnification will show you a lot more.

An important accessory, and I mean this quite seriously, is some means of transportation to a darker sky. Most urban astronomers drive to darker skies regularly.

Can be extended to make progressively more powerful

The key specification for any telescope is its aperture, the diameter of its primary lens or mirror. Do not consider anything smaller than 5 inches (125mm) as it will seriously limit any further expansion. You can start with a reflector on a Dobsonian mount (completely manual) which will give you the most aperture for your money, and then mount it on an equatorial mount at a later date, but you can't "enlarge" a small aperture!

Can use one of the opensource astronomy packages (I am a programmer!)

I'm not a programmer, so can't say much about this. I use a commercial computer program (Starry Night), but not to control my telescopes, as I find the hand controllers supplied with them more than adequate for my purposes. I work with computers all day, and prefer a hobby which does not involve computers!

Allow me to take photographs

I strongly recommend that beginners forget completely about photography until they have learned how the sky works and how the telescope works. As I said above, astrophotography through a telescope is both expensive and difficult, and will distract you from actual astronomy.

I mentioned books. I usually recommend NightWatch by Terence Dickinson as the best beginner's book going. Because of your technical leanings, I'd recommend instead for you the more technical Backyard Astronomer's Guide by Dickinson and Alan Dyer.

There are excellent local astronomy clubs throughout the U.K. Joining a club was the most important first step in my own progress in the hobby.

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For what it's worth I agree with the replies so far. I can relate to where you are coming from - being a programmer myself when I bought my telescope 3 years ago my plan was to do astro photography right from the start, and build my own computer controlled mount etc.

Turns out that taking photos is expensive, and comes more down to equipment than "looking at the stars". I was lucky, and got some good advice - and bought a 2nd hand 10" revelation dobsonian telescope for £200.

Lovely thing, it's big - but is a proper "light bucket", so allows really faint objects to be seen (which most things are!) - for example we were lucky enough to see Triton through it.

My advice - find a local astronomy club, and talk to them. Everyone I've ever spoken to who is into astronomy has always gone out of there way to help - and I'm sure you'll have a similar experience. Go and look through their telescopes and see if you get "the bug" for it, before parting with loads of cash.

You can always send me a message - I'm based in the UK as well, and can provide some more links etc.