I used Jasc Animation Shop 3.10 and Ulead GIF Animator 5.05. Both allow you to import images in various formats and assemble them in to a single animation file with specified resolution, timings and loopings, and text and transition effects. Because multiple images are incorporated in each animated image, file sizes are considerably larger than any of the originals although compression can be used to manage this issue.

To explore the zoom capabilities of a newly purchased digital videocam (Canon ZR-65), I mounted it on a steady tripod and took several trial, still images of a rising gibbous moon. After struggling to keep the moon in a narrow field of view, I set the moon in the lower left corner, I let the earth's rotation do the work, snapping an image about every 30 seconds.

The November 7th aurora provided another opportunity. Using an Olympus 3020 camera that I'd used previously for the northern lights, I shot about 20, 16-second exposures of the northern sky at irregular intervals. So while this animated image doesn't represent a true time series, it does capture the varying greenish glows and reddish pillars I vividly remember from that night. Looking closely you will see that subtle shades are dithered--a limitation of the 256 color palette used in this file format.

From that same camera, I already had several frames of the Southern Cross rising, shot originally to show this magnificent section of the Milky Way. The fact that these combine into an animation is simply fortuitous. The "stars" that don't move between frames are thermal noise from the relatively long exposures used. And just recently, the Moon and planets were in conjunction in the morning twilight. Rather than showing the Moon, Venus and Jupiter rising above Red Mill Pond, what if I took photos from separate days and aligned them to show their relative motion. Now that would be an interesting image!

To capture the sky in motion, all that's needed is a steady tripod, a camera and the ability to count to ten or fifteen. A little forethought helps, but clearly it is not necessary. Little wonder then that animated images are widely used on the web to show motion and change in the sky and across the universe. Some great examples can be found on the Astronomy Picture of the Day web site.

Point your browser to the online version to see the animations. Jerry Truitt’s lunar eclipse animation presented at the November 2004 club meeting provided the inspiration for this edition. Moondark is written by Doug Miller, published at the Moondark web site, and printed in the Delmarva Star Gazers' Star Gazer News. This document was last revised on 31 December 2004. Text and images copyright © 2005 by Douglas C. Miller, All Rights Reserved. This material may not be reproduced in any form without prior permission.