(tiny) movie showing 3D motion of colloids

Lab Home -- People -- Confocal Microscope -- Lab pictures -- Experimental pictures

NOTE: This is from experimental data; the details are discussed below.

It's sped up by a large factor: each separate image is 1 minute apart.

To see a larger version, choose:

medium version (170 K)

big version (360 K)

What I've done: I take lots of three-dimensional pictures (like the one at right) with a confocal microscope. The colloidal particles (2 microns in diameter) that I'm looking at don't move too much between each picture, as is apparent from the animated GIF's. So, for each 3D picture, I figure out where the center of each particle is. Then I assume in the next frame that the new particle closest to an old particle is in fact the same particle. You can download the software I used to track the particles. Shown above are movies of about 60 particles moving, but in fact I'm actually tracking 3000-5000 particles at once (see picture below).

After I tracked the particles, I then took the data and put it into POV-RAY, some nice public-domain 3D visualization software. Then using Gifsicle I converted my images into an animated GIF. I highly recommend both POV-RAY and Gifsicle, they're cool and easy to use.

So why am I doing all this? Click here for a discussion of the physics I'm trying to do.

Picture showing 3000 particles. The image is 60 x 60 x 10 microns.

If you have questions or comments send me email: weeks(at)physics.emory.edu