[X] My Assistant

[MichaelT]

I would like to open this new topic with some Mars images that I obtained using a Philips ToUCam Pro 740k and a telescope. It's really amazing what you can do today with these webcams, a moderately sized telescope and some image processing.

You simply have to unscrew the webcam's lense and fit an appropriate adaptor to attach the cam to the telescope. In this case I used a refractor with 20 cm aparture and a focal length of 3 m. It's the main telescope of Hanover's astronomy club (German homepage) that I am a member of. Additionally I used a 6x barlow lens yielding an equivalent focal length of 18 m.
After finding Mars and focusing, I usually record AVIs which are later split into seperate images (frame rate of 5 Hz).
Then I take 600 frames (2 minutes) and average them with a program called "Giotto 2.0". That program also allows to use various filtering routines to enhance details in the images.
The first image (from left to right) is a raw image, the second the average of 600 frames. To that second image, I apply butterworth and other filters. The resulting images are processed (layers, color adjustments etc) in Photoshop to obtain image 3. A bit of unsharp masking finally yields image 4.


This image is from 22 September (4 UT) The south polar cap is visible to the upper right, Syrtis Major is the large dark area to the lower right. The bright area below the south pole is the Hellas basin. The north pole is veiled by clouds. All the dark areas are not topographic features, but merely differently colored soil. Such detailed images are only possible if the seeing is exceptionally good.

I took images over a period of more than an hour and generated a GIF-animation from them (29 frames, 2:58 UT - 4:03 UT):

Full resolution (900 kB)
From the rotation you can see that the visible structures are real and not artifacts from processing.

One pixel is equivalent to 0.08 arc seconds (~ 33 km). However, the smallest structures visible are certainly larger than that.

Michael