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Comment by _ph_ | Hacker News Reader

Astrophotography without a telescope is indeed a good starting point. Get a bright 50mm lens and just with a simple barndoor tracker you can do amazing things. But as this article is about buying a telescope - and astrophotography through a telescope requires more skill than a complete beginner might imagine.

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You don't even need a tracker at all. Just take a series of 20-second exposures, align them in hugin, and stack them. I have managed to get some remarkably good results this way, because the fact that the star background moves allows you to cancel out a lot of the noise that the camera and light pollution produces.

If the aligning phase can be automated, this looks like a nice plugin for ImageJ/ImageMagick or even an online version in a web page. (You an monetize it with ads about telescopes or something.)

(Bonus points for a deconvolution filter. (Is it useful here?))

Two pieces of gratis software (DeepSkyStacker Live) and RegiStax already do something like this, as well as PixInsight and the venerable Maxim DL, among others.

I did start with a ~50mm lens, but without a tracker. My camera can do up to 30s auto exposures, but those exhibit star trails at 50mm. I limit myself to 10s-15s exposures, and shoot a few hundred of them. The stars move, but the stacker (I use deepskystacker.free.fr) aligns them before stacking them. Though I'll add that DSS has a pretty steep learning curve of its own.

I agree that a beginner can't jump into astrophotography with a telescope. I'm of the opinion that learning with a camera and a tripod will teach a beginner to have reasonable expectations.

For those who don't know, this is what's possible without the telescope and the camera you can use for the other photos too:

https://www.flickr.com/photos/119551085@N06/15418169222/in/a...

Just Sony NEX-6, a tripod and 30 seconds on the (carefully selected) convenient place.

Using image stacking software is also a fantastic tip, big thanks to the sibling comments.

Just that camera, stacking software, and the driest, darkest place on Earth (slight exaggeration) the Atacama Desert.

Excellent photo, though. I'd love to visit a site with such dark skies and good seeing.

Would stacking work for that photo at all? Wouldn't the features on the ground be blurred if you align the stars?

I could believe it's just ISO 1600 and 30 seconds, as the EXIF says?

And you don't need to travel to Chile, just be away from the light pollution and be prepared to make the photos during the moonless night. Use the shooting timer and then you can even have a video of the stars moving, the Milky Way is always impressive:

https://www.youtube.com/watch?v=ZwzY1o_hB5Y

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