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Time Lapse Video of the VLT In Chile

Posted by timothy on from the industrial-light-and-magic dept.

schwit1 writes with a video "captured by Stephane Guisard and Jose Francisco Salgado at the European Southern Observatory's Very Large Telescope (VLT) in Chile's Atacama Desert. And it might make you cry. What makes this time lapse particularly amazing — because we've all seen plenty of time lapse videos of the night sky — is the four telescopes in the foreground. Watching these instruments work against a black background would be endlessly fascinating on its own. Unfortunately you won't be able to pay them too much attention. Because damn, what a sky."

16 of 105 comments (clear)

  1. Why not link to the original video? by Lord+Byron+II · · Score: 5, Informative

    Instead of sending everyone to another blog to view the postage stamp sized video in an embedded player, here's the link to the original video at YouTube:

    http://www.youtube.com/watch?v=wFpeM3fxJoQ

    Nice use of HDR in the video. How did they do that?

    1. Re:Why not link to the original video? by Splab · · Score: 2

      Has anyone physically been there?

      No, those 4 buildings where put there by aliens who also happened to put up a camera and come down to us with it...

    2. Re:Why not link to the original video? by SKPhoton · · Score: 4, Informative

      It actually isn't traditional HDR (where multiple exposures are combined into one frame to create a final image with higher dynamic range.) What you're talking about is somehow gradually increasing the exposure to progressively let more light in as it gets darker as the sun sets. There's currently no magical way to achieve this, but there are a number of different techniques that people have implemented thus far including using light meters to watch the ambient light and either lengthen the shutter speed or gradually stop down the lens aperture, using multiple cameras to bracket different exposures and bounce between the cameras in post-processing, and so on.

      You can read about these techniques in more detail at the very bottom of this tutorial under the header labeled Timelapse "Holy Grail"? Sunset, Sunrise, Day to Night Transitions.

    3. Re:Why not link to the original video? by Goaway · · Score: 2

      With a wide-angle view like that, stars wouldn't visibly streak until you got up to several tens of seconds of shutter time. That is enough time to turn night into day, really.

  2. Im a man with no emotions by jhoegl · · Score: 4, Insightful

    But seeing this made me weep.
    The universe is beautiful.

    1. Re:Im a man with no emotions by perryizgr8 · · Score: 2

      But seeing this made me weep.

      This universe is beautiful.

      ftfy

      --
      Wealth is the gift that keeps on giving.
  3. Re:Mute the sound by RoFLKOPTr · · Score: 2

    Cross-dissolves are annoying and used only by people new to Windows Movie Maker.

  4. You might also want to watch this... by Tasha26 · · Score: 3, Interesting

    A month ago TSOPhotography posted this time-lapse video of the milky way (please watch it in HD). No VLT here and the results are amazing, not to mention the soundtrack... even National Geography forwarded their link. Enjoy :)

  5. Re:stars visible before the sun is gone by phozz+bare · · Score: 2

    The better explanation is this: That's no sun. It's the moon! If you take a long exposure shot on a moonlit night, the sky will be blue and the land will appear sunlit, but there will be stars visible in the sky - just like in this video. Occasionally the moon itself is visible as a very bright spot. Note that when the sun rises the shot becomes completely overexposed, and that's why several scenes end with everything washing out and becoming white.

  6. We're amazing little creatures...aren't we? by Slutticus · · Score: 2

    Busily exploring our world. Wow. It almost brought a tear to my eye....is that weird? Something about watching those telescopes buzzing away with activity against that background....

  7. Re:Orange Laser?? by Nick+Ives · · Score: 2

    Apparently it's a guide star laser: http://www.toptica.com/pr_news/news/news_single/article//toptica-is-awarded-5-mio-EUR-contract-by-eso-for-sodium-guide-star-facility.html

    So I'd guess they use it to make sure they're pointing in the right direction when taking observations.

    --
    Nick
  8. Re:Yellow beams of light? by InfiniteZero · · Score: 2

    Adaptive optics.

  9. Re:Orange Laser?? by ColdWetDog · · Score: 2

    Beautiful video! Does anyone know what the orange laser is used for? Pointing things out to others? Bouncing off the moon? Shooting those pesky UFOs?

    It's an aiming laser. It's sort of described in the ESO website. Seems to help the other telescopes track. Remember that these telescopes are hooked together to form a "Very Large Telescope".

    My original thought was that the astronomers were bored and were shooting aliens, but I guess that's not the case.

    --
    Faster! Faster! Faster would be better!
  10. Reminds me of Hanle by tanveer1979 · · Score: 2

    High altitude observatories are usually located at places with little light pollution, and clean air.
    I have made two trips to Hanle(4400m above MSL)
    For the first visit, we could not see stars as it was overcast(a rare event!)
    However, on the second visit, we did see an amazing sky.
    http://tanveer.smugmug.com/Travel/Ladakh-2010/Chushul-Hanle/IMG3746/906412622_rooft-XL.jpg

    I am told there are some high altitude observatories in Andes mountains(4500m approx)
    2600m above sea level is one of the lowest.

    --
    My Aurora : http://www.youtube.com/watch?v=o91ZsGwJYyg
    FB : https://www.facebook.com/TanveersPhotography
  11. Re:Orange Laser?? by Dusty101 · · Score: 4, Informative

    Yup. As others have pointed out, it's a laser guide star. In a nutshell, the basic idea is that the thing (e.g. a star) that the telescope's looking at gets all smeared out & wibbly wobbly by foreground atmospheric variations (twinkling). The idea here is that if you generate a bright spot in the sky with known properties close to the thing you want to observe, then by comparing what your spot looks like with what you know it should look like, you can calculate which tiny variable distortions you want to add in to the perfect curve of your mirrors to counteract these atmospheric wobbles. The thinking is that if you can correct the wobbles in your fake "star" & it's close to the real one on the sky, then the correction can be assumed to be about the same.

    The actual corrective distortions to the mirror are handled by things that are basically very precise, very small computer-controlled pistons that can apply corrections many per second.

    (For the record, IAAA - I Am An Astrophysicist ,although I've worked at other observatories - not specifically at the VLT).

  12. Re:Orange Laser?? by Anonymous Coward · · Score: 2, Informative

    The shutters regulate temperature; temperature changes make light passing though air "wobble".