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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."

6 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
  3. 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.

  4. 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.
  5. 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.