Webcam Mars picture

Jeff Adkins

Tue, 2 Sep 2003
This is the best image of Mars I've taken. It was taken on Friday, August 29 at about 1 AM Pacific. The equipment and techniques I used were as follows, with references.

The camera was originally based on a Quickcam Express, but since that is a PC-only camera, I removed the guts and replaced them with the parts from a QuickCam 3000 (www.logitech.com), which is cross platform. The camera mount consists basically of a small black project box with a 1 1/4" outside diameter tube attasched to a hole in the box; the CCD chip lies in the bottom of the hole, surrounded by black electrical tape to absorb stray light.

The telescope I and a couple of friends, Ray Kuntz and Eric Chamberlain, used was a 10" Meade SCT, specifically an LX200 GPS, which is pretty fun to use. This telescope aligns itself, or nearly so. All you have to do is verify a couple of stars and presto, you're in business. Basically I centered Mars, then moved the image down in the field of view until it matched the relative position of the CCD in the tube, popped out the eyepiece, put in the camera, refocused, and started recording. There was a 2x barlow in the light path for this image.

Using IOxperts' Quickcam driver (http://www.ioxperts.com) and BTV's image capture program (http://bensoftware.com) I make short Quicktime movies in real time of the Red Planet. Here is a sample frame from that movie:

When doing this sort of observing, it is important to save your work frequently.
Finally, using a program called Keith's Image Stacker, I selected about 20 of the best frames from the movie, then nudged them around so they were lined up nearly in the same position. Then the software added the images together and produced a raw image not too different from the picture above. Watching the resulting video is very similar to looking directly through the eyepiece yourself. Keith's Image Stacker does all the thing one learns about in a course in astronomy on CCD's: dark frames, bias, etc.
I intend to register all the the shareware mentioned above soon, so I can run longer sessions without being interrupted by shareware notices.

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