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View Full Version : OT: Snow flake photos and some science



wierdscience
12-17-2008, 10:59 PM
Neat group of pics,had no idea there were so many designs-

http://www.newscientist.com/gallery/dn16170-snowflakes/1

More here-

http://www.its.caltech.edu/~atomic/snowcrystals/photos/photos.htm

ZINOM
12-17-2008, 11:51 PM
Those are cool, I don't have any fancy equipment but I took some pics last year of some snowflakes in my back yard...the amount of flakes wasn't much, but they were amazing in their "snowflake-ness"

The pix on the top left of the page were just random flakes on a tree stump...one I shot through an eye loupe with my cybershot.
http://www.mpiretattoo.com/misc.htm


It looked more like someone had sprinkled stuff from a party store or confectioners shop as opposed to the kind of snow I've seen all my life living in Rhode Island....they were almost all this distinguishable as single, "traditional" flakes and not clumps or bits.

Sorry to hi-jack the thread, just wanted to share .

John

hornluv
12-18-2008, 12:10 AM
There was an article in Popular Science a few years back about photographing snowflakes. I think it was the Gray Matter column. Anyway, when a snowfall was expected, the author would put a bunch of microscope slides outside so they would be at the same temperature as the air, then he would catch snowflakes on the slides and put a drop of super glue over the flake. The glue would react to the water and harden, leaving a perfect impression of the flake that could then be photographed and ogled over for all time without all that pesky melting.

nheng
12-18-2008, 12:20 AM
Wierd, Thanks for the happy stuff to pass around ... I got my slides ready to go.

Will post pictures if they work, eat snowcones if they don't :D Den

jcarter
12-18-2008, 12:45 AM
Yet another excellent example of the beauty of nature. Not so much fun when you are up to your crotch in it and have to shovel it. We have another foot of the crap on it's way tonight.

Greg Menke
12-18-2008, 07:23 AM
I went to a colloquium a couple years ago where IIRC pictures of snow taken by electron microscope. It was really fascinating, all kinds of symmetry and detail all the way down. The guy who did the work as able to photograph snow samples from all sorts of conditions from loose to compacted and at various temperatures. Fascinating presentation.

Regards,

Greg

Evan
12-18-2008, 10:25 AM
For anyone interested in atmospheric visual phenomena caused by ice crystals there is an excellent free simulator called Halosim here:

http://www.atoptics.co.uk/

It will simulate all the possible arc, halos, azimuthal rings etc that can be produced. This is an example of a Parry Arc. I have a photo somewhere that I cannot find of this extremely rare sky phenomena. This is from the program Halosim.

http://metalshopborealis.ca/pics5/halosim.jpg

aboard_epsilon
12-18-2008, 10:54 AM
Never understood this snow flake business .....

I cant understand it at all

all the average human sees is a large blob

you can see the patterns in frost on windows .thats it for me.

but you ain't ever with the eyeball ...at least my eyeball, going to see any paterns.....so why all the fuss that is dedicated to it ..

all the best.markj

Evan
12-18-2008, 11:07 AM
I'll give you one example of how ice crystals drifting in the winter air around here provide a very nice benefit to night driving. When it is as cold as now even when the weather is clear there are ice crystals in the air because the last bit of water vapor is freezing out and drifting down. On truly cold days with the sun shining bright at -40 it will be ever so lightly snowing from a clear blue sky.

At night these crystals refract the light from oncoming headlights as two very tall vertical columns of light that can be easily seen even when the approaching vehicle is on the other side of a hill.

wierdscience
12-18-2008, 10:06 PM
I was watching the snow fall here the other day and noticed something.Most of the flakes were about 1/4-3/8 diameter,but occasionally one very large flake maybe 3/4-1" would fall.I caught one on my jacket arm and in the instant before it started to melt I did see it was a single flake and had a distinct pattern.

Judging by the size of some of the rain drops we get here,I would hate to see it snow in the summer:)