|The Astronomical Society of Greenwich||
Bruce Museum, Museum
Greenwich, CT 06830 (203) 869-6786, Ext. 338
Astronomical Society of Greenwich info
I have been using a modified B&W QuickCam to take images of the Sun, moon, and planets. I turned my attention to Mars during May of 1999. It was the closest Mars was to the Earth in 9 years, and I wanted to try out this new 'secret weapon'. I have to say without hesitation that CCD imaging is the only way to go for the planets. Here's why…
In a few minutes you can take about 500 images. Since each image is 6k in size, you can fit them on 2 floppies uncompressed. Then, back in the warmth of your house, you can sift through and pick out the best 16 images. This is what makes imaging such a potent weapon in the quest for the elusive perfect image. It's like a poor man's interferometer.
I call it a pyramid stack, because all of the 16 contribute equally to the final image, and the stacking process resembles an upside down pyramid. I find that 16 works best, but you could use 8, or 32 images as well. Besides stacking the images, they are sharpened and tweaked with software to bring out detail that can't be seen in the raw images.
|The May 11th image was taken through 6-10 seeing. It is centered on Mars' central meridian 63. This image is a good representation of what Mars looked like during those fleeting moments of good seeing. It's a stack of 16 images (best of about 500) taken through a 12.5" reflector w/2x Barlow at the Bowman Observatory.|
|The May 20th image was taken under the exact same conditions and equipment except I had about 600 images to choose from. The central meridian in this image is 318. Both images can be compared to Mars maps found in April 1999 Sky&Tel and features identified. I find that personally very rewarding.|
I will continue the quest for the evasive perfect image. Although I haven't yet achieved perfection, (and of course never will) I'm very happy with the results so far. Up next… Jupiter!