3D Without The Glasses

A Wiggle Stereogram

A couple of weeks ago, I blogged about a screencast I did that showed how you could convert stereographs into red/blue 3D anaglyphs. Jim Gasperini has a nice writeup about “wiggle stereograms”, basically two frame animated gifs which toggle back and forth between two images.

On the right, you can see that I created one of these pretty quickly using the Gimp. Basically you take the left and right images, load them into two different layers, preview them using the Filter>Animation>Playback tool, and then save the result as a gif, and check the box that makes you save them as an animation.

Kind of neat!

read more | digg story

Color Photos taken 96 years ago!

This post does two things. It provides a link to a cool collection of antique color photographs taken by Sergei Mikhailovich Prokudin-Gorskii, and also tests my ability to use digg to directly post interesting articles to my blog.
I wonder how well it will work.

Assuming this works, in the future I’ll try to include more bonus information, such as this link to a class project that utilized these photos.

read more | digg story

P.S. it worked.

Supercooled Water

Courtesy from digg, check out this article with video dramatically demonstrating the freezing of supercooled water.

If you ask most people with the freezing point of water is, they will confidently answer that water freezes at 0 degrees Celsius (or 32 degrees Fahrenheit if you are in a backward country that never shifted to the metric system). But what many people don’t know is that water can exist in liquid form at temperatures which are significantly lower than that. I first remember reading about this in Craig Bohren’s excellent book Clouds in a Glass of Beer: Simple Experiments in Atmospheric Physics. It’s a great book detailing many of the processes that govern weather. He mentions an experiment where you place a small plate with several individual drops of water on a plate and place it in your fridge. You will find that many remain in liquid form for a considerable period of time, and that mechanical jostling of them can cause them to instantly freeze. The video on the webpage above demonstrates some of the same ideas, but much more dramatically.

Cool stuff with a nice writeup.

SETI@home a security risk?

This rather wacky report talks about the possibility that ETs could infect the earth’s computers with viruses by transmitting certain signals which cause (say) buffer overflows in our computers and infect the internet.

Dr. Carrigan thinks that the SETI scientists should implement some kind of decontamination procedure to clean the signals before they are distributed.

It seems kind of obvious to me that if we knew enough to conclude that a particular signal was trying to act as a virus, we’d have pretty strong proof that extra-terrestrial intelligence was a reality.

I tried to locate the actual article, but could only find this link to the abstract.