Forgot your password?
typodupeerror
Science Technology

High-Speed Camera Grabs First 3D Shots of Untouched Snowflakes 79

Posted by samzenpus
from the in-mid-air dept.
sciencehabit writes "Researchers have developed a camera system that shoots untouched flakes 'in the wild' as they fall from the sky. By grabbing a series of images of the tumbling crystals—its exposure time is one-40,000th of a second, compared with about one-200th in normal photography—the camera is revealing the true shape diversity of snowflakes. Besides providing beautiful real-time 3D snowflake photographs from a ski resort in Utah, the goal is to improve weather modeling. More accurate data on how fast snowflakes fall and how their shapes interacts with radar will improve predictions of when and where storms will dump snow and how much."
This discussion has been archived. No new comments can be posted.

High-Speed Camera Grabs First 3D Shots of Untouched Snowflakes

Comments Filter:
  • by Anonymous Coward

    So who else found the penny?

  • by girlintraining (1395911) on Thursday April 11, 2013 @07:31PM (#43428317)

    ...Moments later, the pictures were uploaded to Instagram with a vintage filter, and ceased being cool.

    • by ackthpt (218170)

      ...Moments later, the pictures were uploaded to Instagram with a vintage filter, and ceased being cool.

      And then Mark Zuckerberg formed a new polical lobby for Snow Flake Preservation.

      • by girlintraining (1395911) on Thursday April 11, 2013 @08:02PM (#43428555)

        And then Mark Zuckerberg formed a new polical lobby for Snow Flake Preservation.

        Zynga then promptly released a game where you can buy virtual snowflakes to drop on your farms, but was sued by Apple for patent infringment over it's slide-to-drop snowflake technology. Microsoft released a snowflake player called 'Snune', but was widely panned by critics as being inferior to all other offers. A few weeks later, it quietly disappeared. Regular slashdot readers blamed stagnancy in cloud technologies for the lack of high performance snow, and girlintraining continued to snark the crap out of everything she comes across...

    • "...Moments later, the pictures were uploaded to Instagram with a vintage filter, and ceased being cool."

      Actually, I don't think you need an instagram filter to make these pictures uncool.

      I've seen lots of crystalline snowflakes under magnifiers and microscopes before, and they look nothing like these pictures. The ones I saw had nice sharply-defined edges, but these -- including the nice symmetrical ones -- are noticeably fuzzy around the edges.

      No doubt, this is an improvement allowing us to get a look at lots more kinds of snowflakes. It's just that they're actually pretty shitty pictures.

      • The ones I saw had nice sharply-defined edges, but these -- including the nice symmetrical ones -- are noticeably fuzzy around the edges.

        The pictures are absolute crap, so there's no real way to tell if the (symmetrical) flakes are actually fuzzy around the edges, or if it's the horrid pixelation, or the focus/depth of field problems, or... well, you get the picture.

        (So I wouldn't go on about Instagram, because you haven't a clue what you're looking at or talking about.)

        • "So I wouldn't go on about Instagram, because you haven't a clue what you're looking at or talking about."

          What the hell are YOU talking about?

          I wasn't "going on" about instagram at all. I was simply discussing the quality of these pictures versus OTHER pictures and micrographs I have seen of actual snowflakes. And I have seen many.

          It was GP who was joking about instagram. If you have an issue, go talk to her.

          • It was GP who was joking about instagram. If you have an issue, go talk to her.

            Try reading your own messages sometimes - I wouldn't have brought up instagram if you hadn't.

            I was simply discussing the quality of these pictures versus OTHER pictures and micrographs I have seen of actual snowflakes.

            Um, no. Try reading your own messages sometimes. You were discussing the features of the flakes as seen in these images.

            • "Try reading your own messages sometimes - I wouldn't have brought up instagram if you hadn't."

              Jesus Christ. Do you have reading comprehension issues? Here is a quote of my first sentence. Emphasis added:

              "Actually, I don't think you need an instagram filter to make these pictures uncool. "

              This was in response to someone else's joke about Instagram. Are you reading the same words I am? Where in that sentence of mine is there anything negative about Instagram?

              "Um, no. Try reading your own messages sometimes. You were discussing the features of the flakes as seen in these images."

              Um, yes. Repeat, again:

              "I've seen lots of crystalline snowflakes under magnifiers and microscopes before, and they look nothing like these pictures. The ones I saw had nice sharply-defined edges, but these ... -- including the nice symmetrical ones -- are noticeably fuzzy around the edges... It's just that they're actually pretty shitty pictures."

              Repeat again: it is a discussion of these pictures VERSUS OTHER PICTURES of snowflakes I have seen. It is right there in plain English. Same as I wrote it the first time. In context, no changed words.

      • by Synerg1y (2169962)

        It's pretty crazy how complicated such a seemingly simple thing as photographing snowflakes can be.

        • I agree. And I wasn't disparaging this technology, which may well turn out to be valuable. But let's face it... the pictures aren't of wonderful quality. No doubt that will improve.
          • by Synerg1y (2169962)

            I was slightly amazed that the camera they're using... something way way above consumer grade wasn't able to get the job done to a level of high quality, I agree, the pictures are kind of grainy and its hard to tell the actual shape on some of them.

  • by Anonymous Coward

    rather than the bs from sciencemag?

    here it is:

    "MASC Showcase: Snowflakes in Freefall

    For more information about this University of Utah and National Science Foundation project please visit the Snowflake Stereography and Fallspeed home page or email Tim Garrett.

    This is a gallery of snowflake images captured in freefall at Alta Ski Area using the University of Utah MASC (Multi Angle Snowflake Camera). When it is snowing, images of snowflakes captured live in free fall can be found at Alta's Snowflake Showcase.

  • Don Komarechka (Score:4, Interesting)

    by Flammon (4726) on Thursday April 11, 2013 @08:41PM (#43428779) Homepage Journal

    I have a cousin who's writing a book on this.

    http://www.indiegogo.com/projects/sky-crystals-unraveling-the-mysteries-of-snowflakes [indiegogo.com]

  • by Anonymous Coward

    From the article:

    The classic image of a snowflake is a fluke. That flat, six-sided crystal with delicate filigree patterns of sharp branches occurs in only about one in every 1000 flakes.

    Wrong. The six-sided snowflake is a particular type of snow that occurs in specific conditions. When conditions are correct, you'll see endless amounts of six-sided snowflakes. Source: I live in the Canadian Prairies.

    • by sarysa (1089739)
      A good portion of the snowflakes on the site were six sided or clearly used to be six sided. Expecting the level of precision (that they are implying) in nature is ridiculous, though....
  • by The_Rook (136658) on Thursday April 11, 2013 @09:01PM (#43428871)

    what i've always wanted to know was why are snowflakes symmetric?

    sure, a hexagonal crystal has bilateral symmetry etc. but snowflakes form long, complex arms with what can best be described as filigree. and yet, the filigree on opposite sides of the snowflake are also symmetric - that's shown even in these photos.

    so what i want to know is how does crystal faces on opposite sides of the snowflake 'know' to grow symmetric filligree? what mechanism is there that allows one crystal face of a snowflake to 'know' what the other crystal faces are doing and so grow identical structures?

    • by exploder (196936) on Thursday April 11, 2013 @09:34PM (#43429027) Homepage

      I think it's because (snowflakes being quite small) all sides experience nearly identical conditions of temperature, humidity, whatever-else-affects-crystal-growth at nearly identical times.

      • by Anonymous Coward on Thursday April 11, 2013 @10:09PM (#43429213)

        I think it's because (snowflakes being quite small) all sides experience nearly identical conditions of temperature, humidity, whatever-else-affects-crystal-growth at nearly identical times.

        I'm a cloud physicist and you, sir, are correct, identifying not only the reason for the symmetry (uniform conditions across the crystal over relevant time scales) but also the two controlling factors of temperature and humidity (well, humidity above saturation). Well done. Let me buy you a virtual beer.

        The diversity of shapes is what's really cool. As far as I know (and this isn't my area) we have a phenomonology for habit (we know what shapes are most likely at a given temperature and humidity [doi.org], for example) but we don't have a good theory to explain why that's so.

        • by pspahn (1175617)

          Just to add to this, there is a cave in Colorado that I found last summer (it is known of, but it sees very little visitors... maybe a dozen a year) that apparently develops very rare ice crystal shapes in the winter near the entrance. What I read is that it is one of only a handful of places in the world where this is known to occur.

          • by Jon Abbott (723)

            Do you mind sharing where? I'm doing a photography book on Colorado and would like to include such a place. My email is i_love_junk_email at yahoo.com.

            • by pspahn (1175617) on Friday April 12, 2013 @01:47AM (#43430155)

              Can't remember the name specifically, it is almost exactly at 39.518712, -106.629701

              There are some yurts just to the west about a 1/4 mile. I suggest staying there (Hidden Treasure Yurts) and reading the great binder full of information on local caves. I read the article about this specific cave, and it's quite fascinating.

              If caving in Colorado, please educate yourself on White Nose Syndrome. It is not prevalent here, and people would like to keep it that way.

              • by pspahn (1175617)
                Ah, Devil's Den cave. Note, you'll probably not find much info online about it... there is a popular cave in Arkansas with the same name.
                • by Jon Abbott (723)

                  Great, thanks. It's definitely a drive from where I'm at but hopefully I'll make it out there sometime.

                  • by pspahn (1175617)

                    If you go in winter, access by snowshoe, snowmobile, or skis... there's no other options.

        • Thanks for the doi link! I'm amazed I can download the PDF without being at a university connection. The "habit diagram" in figure 2 of that paper is really cool. And figure 5 with Temperature vs. "Ice supersaturation" (? not fully understanding that) with the illustrations of the crystals that form at different variations of X vs. Y in the atmosphere or in their "diffusion" chamber. Very nice article.
        • by funkify (749441)

          TFA mentions that a "classic" snowflake only occurs about once every 1000 flakes. Here in the Rockies, I have observed that many snowstorms produce no noticeable "classic" snowflakes, while in other snowstorms, nearly every flake that falls is a "classic" snowflake.

          Can you, Mr. Cloud Physicist, enlighten us on this?

    • by c0lo (1497653)

      what i've always wanted to know was why are snowflakes symmetric?
      how does crystal faces on opposite sides of the snowflake 'know' to grow symmetric filligree?

      Possible explanation not involving "knowing": if they are asymmetric, they break due to difference in air drag forces over the asymmetrical branches (?!?? something like "snow flake evolutionary pressure"?)

    • by dbIII (701233)
      Less energy to do so.
  • Bad summary (Score:5, Informative)

    by TrumpetPower! (190615) <ben@trumpetpower.com> on Thursday April 11, 2013 @09:06PM (#43428907) Homepage

    First, 1/200s is a very common shutter speed, yes, but most cameras can shoot at at least 1/2000s and most high-end cameras can shoot at 1/8000s...assuming, of course, you have enough light.

    Most high-speed stills photography is actually done with a slow shutter speed; perhaps even a shutter left open for a couple seconds. Motion is stopped by the short duration of the flash burst. And with, for example, a Canon 580 EX II flash, you can get a 1/35,000s flash duration. Granted, this will be at minimum power...but they're operating at macro distances, where you can put the flash head almost on top of your subject and still overpower the subject with light.

    Don't get me worng; this team is doing some nifty stuff. But it's also something that most professional photographers could easily replicate with the equipment they already have -- and that anybody who specializes in macro photography will probably already plan on playing around with next winter after reading this article.

    What the team is doing that's interesting isn't the photography. It's the 3D reconstruction and subsequent analysis and modeling. Making it seem that it's about the photography, which is the easy and inconsequential part, really detracts from the good stuff.

    Cheers,

    b&

    • by Anonymous Coward
      The original researchers do point out that they are using off the shelf cameras for th individual views within the 3D setup, and that they're nothing particularly special (as opposed to say an off the shelf ICCD camera with exposure times in the nanoseconds). They discuss why they didn't go with high speed flashes and instead used cameras that could directly use such exposure times: low power so it can run off a small batter at,repetition rates of up to ~1 Hz for long periods of time and resilience in a co
      • by muridae (966931)

        That's something I can't figure out, though. You have a falling object, and a moving shutter that I hope is moving vertically downward. A sideways moving shutter should create some amount of distortion at 1/40,000 of a second. Even a vertical shutter should have some lag, unless I'm vastly mistaking the moving rate of a snowflake.

        As a note for the non-photographers, high speed shutters do not open and close completely at 1/40000th. The normal method of off the shelf equipment is that the shutter opens, and

        • Re:Bad summary (Score:4, Informative)

          by rgmoore (133276) <glandauer@charter.net> on Friday April 12, 2013 @01:59AM (#43430191) Homepage

          The trick is that the shutter isn't doing the work; the flash is. It's possible to make very short flash pulses; I think you can make them even shorter than the 1/50,000 second mentioned in the article. As long as most of the light for the photograph comes from the brief but intense flash, the ability to freeze action depends on the flash speed rather than the shutter speed. You actually need to make sure the shutter speed is slow enough that the shutter is guaranteed to be all the way open when the flash triggers (X-sync speed or slower), or only the area behind the open part of the shutter will be exposed. Controlling things using the flash also guarantees that the multiple cameras used for 3D photography will all be taking their pictures at exactly the same instant.

          Also note that the limitation you're talking about only applies to focal plane shutters (i.e. those right in front of the film or sensor). It's also possible to use a central shutter that's located right next to the iris of the lens. Central shutters open and close like the lens aperture, but block the lens completely when they're closed. Like the lens aperture, they block light to all parts of the focal plane more or less equally as they open and close, so they don't induce any of the motion effects that focal plane shutters do. Central shutters have their own problems- it's hard to make them work for very short shutter speeds, and they have limited efficiency when you use them that way because they're only completely open for part of the time- but they do eliminate focal plane shutter artifacts and allow you to flash sync at any available shutter speed.

    • by Jon Abbott (723)

      Agreed. Humorously enough, as I read your post, I saw the mention of Canon, then looked at your username and remembered seeing the same username over at CanonRumors.com. I also frequent that site... small world.

  • Still facsinating (Score:5, Interesting)

    by Ogive17 (691899) on Thursday April 11, 2013 @09:25PM (#43428991)
    I'm 33 and on occasion I'll see one of those perfectly shaped snowflakes land on my coat, after all these years I still think they are cool.

    I just wish its trillions of friends would get off my lawn (and driveway).
  • Who would have thought you could photograph a snowflake?
  • by TheSkepticalOptimist (898384) on Friday April 12, 2013 @09:46AM (#43431657)

    Someone cried out "Oh I have wasted my life...!"

RADIO SHACK LEVEL II BASIC READY >_

Working...