Previous Uploads: Three faces of Comet Linear Comet Linear A2 6-27-01 Van Cittert Deconvolution of the Lunar Highlands More Northern Lights and the ISS over Payson The NGC891 Galaxy Group Notes CCD Shots during Full Moon Comet Linear July 19 & 25th, 2000 Latest image of Comet Linear S4 Spectacular Red Aurora over Payson Arizona Fuji's New Formulation of it new Super HQ100 FIRST TESTS OF HYPERED FUJI HQ100 First Schmidt shots with PJ400 First Tricolor shots with 2415 Test Images with Fuji NPH400 First Two Comets with the new CCD Camera
One of the greatest challenges in high resolution astrophotography is getting cooperation from the Earths own turbulent atmosphere. In recent years, a number of masking and sharpening routines have become common place amongst astroimagers to bring out the fine details the atmosphere smears. Tracking errors as well contribute to this problem, and for this case was compounded by a shaking tube from a noisy stepper motor in the RA axis of my AP1200 QMD mounting. These two images represent the before and after of using AIP for Windows new Van Cittert deconvolution algorithm. Instead of just sharpening or high pass filtering the image, deconvolution attempts to restore the original image information based on an estimate of the blurring transfer function of the atmosphere. I have tried many software packages for this function and AIP appears to have by far the best VC and RL algorithm interfaces around. If you only get the software for the book and these two functions, its worth it!
The images:
First image, this shot has been only adjusted for contrast and brightness, a direct shot with my 12.5 inch f/5 Newtonian, on my ST7E and a neutral density filter. A .11 second exposure was used to freeze the seeing, and out of a dozen frames, these four were selected, and median combined to form this image.
This second image, is the same image but with only 20 iterations of AIP for Win Van Cittert deconvolution. The results speak for themselves. To make what was a rather flat looking shot more photographic, I adjusted the gamma as well afterwards.