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Amateur Astronomer Grabs Amazing ISS Picture

Posted by samzenpus on from the good-focus dept.

The Bad Astronomer writes "Ralf Vandebergh is an amateur astronomer, and using a simple telescope with a video camera attached to it, he took an incredibly detailed picture of the International Space Station. You can easily see the recently-installed truss and solar panels, as well as the Space Shuttle Discovery docked to the station."

12 of 80 comments (clear)

  1. Par for the course... by Wiener · · Score: 5, Informative
    Ralf, quite simply, takes amazing photos. From what I understand, these are manually tracked snapshots.

    He has a number of photos posted at Cloudy Nights in the "Planetary and Solar System Observing" forum.

  2. A simple technique taken to an extreme by The+Hooloovoo · · Score: 5, Informative

    He basically used a method reminiscent of a technique used by amateur astronomers to take pictures of planets and asteroids: take a lot of frames using a cheap webcam and stack them together, weeding out the bad ones as you go.

    The principle behind it is pretty simple. When it comes to seeing nearby planets (Pluto and friends are obviously exceptions), telescopes are limited less by magnification and more by atmospheric distortion. What's not clear from the article is if this is a single frame grab (which is pretty cool but not an incredible technical feat) or if he managed to track it precisely enough to stack a few frames.

    1. Re:A simple technique taken to an extreme by Skapare · · Score: 4, Informative

      Stacking frames does not require precision tracking. You only need to track it well enough to keep it in the frame. And in some cases partially out of the frame still has limited usefulness. The software correlates the positions based on what is in the picture. If there's enough of a pattern to make the alignment (at sub-pixel resolution), then it's easy. If it's fuzzy, you might have to do the alignment manually.

      --
      now we need to go OSS in diesel cars
    2. Re:A simple technique taken to an extreme by david.given · · Score: 3, Informative

      ...take a lot of frames using a cheap webcam [wildimaging.co.uk] and stack them together, weeding out the bad ones as you go.

      You might be interested to have a look at some software called ALE, which can be used to do this more or less automatically; you give it a sequence of frames and it'll synthesize a superresolution image combing data from every frame.

      (You can also use it to generate panoramic images from video pans --- it automatically locates, rotates and transforms every frame correctly, figuring everything out for itself!)

      The only problem with it is that it's really slow, so you'll probably want as big a computer as you can humanly manage.

      One day I should try taking some simple digital camera footage of the moon and running it through ALE just to see what happens...

  3. On a clear night... by pallmall1 · · Score: 2, Informative

    ...you can see forever.

    --
    3 things about computers: they're alive, they're self-aware, and they hate your guts.
  4. Re:If they want to save power by MeanMF · · Score: 4, Informative

    It's blurry because it's taken through miles of atmosphere. That's why Hubble is in orbit and most observatories are on top of mountains.

  5. What about Rayleigh Criteria? by NotSoHeavyD3 · · Score: 4, Informative

    I mean I wouldn't be surprised if he was getting pretty close to that limit. http://en.wikipedia.org/wiki/Rayleigh_criterion#Explanation To make that short I kind of remember this from my physics class that ultimately the limit on being able to differentiate between 2 objects depends on the size of your main mirror/lens and the wavelength of light you use. (IE a bigger main mirror or shorter wave length of light means you can differentiate between closer and closer objects.) If I remember correctly I did the math and found out that you'd need a mirror about 250 meters across to resolve the landing site on the moon from an earth based telescope. (But I can't remember if that resolution was 1 meter or 30.)

    --
    Did you know 80 to 90% of the moderators on slashdot wouldn't recognize a troll even if one dragged them under a bridge.
  6. A mirror -- just in case by The+2nd+.+Oracle · · Score: 2, Informative

    http://blogs.discovermagazine.com.nyud.net/badastronomy/2009/03/25/shuttle-and-station-imaged-from-the-ground/

    Funny how nyud.net has disappeared from /. in the last few years. I kinda miss the reliability. It seems like twice a day some poor website is blasted half way around the world because of /., why not use nyud.net some more?

  7. No Subject by Orphaze · · Score: 4, Informative

    It's certainly a good image, but not the best. This image of Ralf's, for instance, is noticeably more clear. He has many more amazing images though on his site here.

    1. Re:No Subject by LateArthurDent · · Score: 2, Informative

      It's certainly a good image, but not the best. This image of Ralf's, for instance, is noticeably more clear. He has many more amazing images though on his site here.

      Holy shit. There's a picture of his on that site which actually managed to capture an astronaut on a spacewalk. Talk about impressive.

      Thanks for the link, there's a whole lot of very interesting shots there.

  8. Re:Vandeberghâ(TM)s 25 cm Newtonian Telescope by The+Bad+Astronomer · · Score: 3, Informative

    It's a 10 inch mirror. I owned a 'scope like that for over 20 years, and it's a pretty decent instrument. It looked like a water heater; a foot across and two yards long.

    --
    *** Phil Plait, aka The Bad Astronomer http://www.badastronomy.com
  9. Re:If they want to save power by digitalchinky · · Score: 2, Informative

    Probably a good deal of that blur can be removed though - there are some stunningly detailed images of area 51 from 26 miles away taken through a telescope using multiple images to remove the atmospherics:
    http://www.dreamlandresort.com/area51/panorama_0608.html

    Naturally this would be a little more challenging with the ISS since it's moving pretty fast through the scope - probably need a motor drive on it to keep it steady.