Starting out in astrophotography – what sort of scope?

The awful choice in astrophotography

For astrophotography, some things in the sky, like nebulas, are surprisingly large but incredibly dim. These need telescopes with lots of light gathering ability but low magnification. On the other hand, planets are tiny objects which shine very brightly. Of course, they need the complete opposite, telescopes with masses of magnification with light gathering ability being less important.

The upshot of this is that there comes some point in every astrophotographer’s career when they’re going to have to make a choice. What types of targets are you going to specialise in? Are you a planet watcher, watching storm clouds cover the surface of Mars, Jupiter’s Great Red Spot, or that weird hexagon-shaped cloud that rotates around Saturn’s pole? Or, like me, are you intrigued by the swirls and convolutions of gas clouds that lurk between stars, or the dust lanes that encircle galaxies outside our own?

My advice is, before you get to the point where you’re forced to choose, take some photos with whatever you have. That way, you’ll get an idea of what photography is going to be like, so you can then plan your next development. The thing you want to avoid is to buy stuff you don’t end up using.

Start with the Moon. It’s nice and bright so you can use short exposures – you can even use automatic exposure on your DSLR. Then increase the challenge and photograph Jupiter or Saturn. They’re bright but small. Don’t even think about tracking yet. Astrophotography is hard – other people have told me that it’s the most difficult branch of photography there is.

My first astrophotography telescope

I’ve been interested in astronomy since going to a school with a club that had a couple of telescopes. As I got older, I developed an astigmatism. With this eye problem I wasn’t really able to look through an eyepiece without glasses. So I decided to get into photography, where I didn’t have to actually focus on the object, but rather, play with the image.

My first telescope that I used for astrophotography was a 6” Cassegrain. It had an early version of an alt-azimuth go-to mount. It also had a focal length of about 1500mm so I had lots of magnification to play with. My wife and I bought this for her school. She’s a science teacher and wanted a telescope that was easy to set up and run at open nights.

I found I could take photos with my own DSLR using a Pentax t-ring and adapter. Using this kit, I got some pleasing photos of planets like Jupiter and Saturn, as well as bright nebulas like M42.

Jupiter and Saturn

The equivalent telescope today would probably be a Celestron Nexstar 6 SE. This is a very similar telescope, with an alt-az go-to mount, and the focal length is also 1500mm. The photos would be probably very similar. That is, I could get those photos for under $1800.

My second astrophotography telescope

Where did I go from my alt-az go-to Cassegrain? Well, as always with upgrades, I didn’t have much money, and I wanted to get the best bang for my buck. I upgraded the mount, and lashed out for the NEQ6 pro that I still have today. Honestly, I bought it from Optics Central. I had to do some dodgy work with a drill to take the tube off the old fork mount and put it on the new one, but wow – the difference decent tracking makes!

Since then, I’ve upgraded in dribs and drabs. There are a pile of advantages with this. First, you don’t have to spend a heap of money all at once, which is always good. Second, you can think about your next upgrade for a good long time, meaning you don’t make rash purchases. Third, and one I didn’t even think about, was that you get practice at your latest upgrade before getting to the next one. A while back I upgraded my camera to a monochrome with filters at the same time as moving to Sequence Generator Pro software. Oh my, the confusion!

By the way

I feel a bit sheepish about showing my own ancient photos. The thing is, though, practice makes perfect. Compare my first photos with some produced by an expert who has had a heap of practice. The difference would be enormous.

Just as a comparison, here’s a photo I took lately of the Tarantula Nebula (next to the Large Magellanic Cloud). I still need help in processing, but people are eager to help me learn.

Tarantula Nebula astrophotography

So never, ever, be discouraged by your first photos. You might have trouble looking beyond their faults. But take it from me: everyone else will be stunned by how good the shots are.

Astrophotography software I needed to know about

The photos I’ve put above aren’t exactly as they came out of the camera. There’s a dirty little secret that all astrophotographers know about that others don’t. No, it’s not fight club, it’s image stacking software. Take something like 1000 photos using your DSLR (and you can use movie mode if it’s a bright target). Then give them to your computer to process. The magic of mathematics means that your computer can cut a lot of fuzz from the photos you give it. What you get back is simply amazing. It makes the difference between a blob and Jupiter.

There are several different programs you can download and use for free. Don’t even think about spending a cent on more sophisticated software yet. Because different programs have different uses, there’s a lot to be said about them.

So my recommendation?

While the Celestron isn’t the most expensive scope in the shop, it’s still a bit of a stretch for most budgets. I think that the Skywatcher Star Discovery 127/1500 would have given me as good an image as the Celestron for the planets. With practice, of course. Because planets are very small but very bright, you can get a smaller and less expensive telescope, as long as there is enough focal length.

On the other hand, I don’t think the photo of the Great Nebula in Orion would have been as good with the Star Discovery 127/1500.

Your turn

Now it’s time for you to write back.

What was your first telescope? Have you upgraded? How did you upgrade, and what’s next? What would you have done differently?

If you haven’t got your second scope yet – which is it going to be?

And most importantly, why?

Bill is Optics Central’s expert on astrophotography, telescopes and bird watching. You’ll find him in the Mitcham store on Fridays and Saturdays. Come in for advice on how to get the best out of your current telescope, what your next telescope should be, how to take photos of the sky, or even how to see some rare birds.

Leave a Reply

Your email address will not be published. Required fields are marked *