Now at 5.5 magnitude and holding steady, this fast moving comet in Cetus is plunging directly for the southern horizon. The comet was not visible easily naked eye, and exposures had to be kept no longer than 30 seconds each as to not blur the comet from motion. This image is an LRGB, composed of thirty 30s exposures with a clear filter added in Maxim with the nucleus in register. The streaks are the stars trailing by. The color was the same exposure, but binned 2x2 with the RGB filters. The characteristic green color of comets can be seen in this image as well, the leading edge of the coma always the most strongly colored. Some luminance posterization is unavoidable due to the limited dynamic range of each short 30s sub exposure.
The two images below represent two different approaches to processing comet images which are commonly used for showing details unseen by conventional processing. The left image, is processed in AIP with the Rank Multiply filter. This is used to bring out subtle details such as this very prominent ray emanating from the nucleus.
The second image to the right is processed in AstroArt, using the Larson-Sekanina filter, especially developed for comets. This is not really a filter, but a transform function where the image is rotated 15 degrees about the nucleus, and subtracted from itself. What this shows is any details that are not symmetric about the nucleus, such as this fan tail.
Previous Uploads: New images of Linear WM1 11/09/01 Another Major Northern Lights Display from Payson, Arizona The fading comet linear A2 More lunar Closeups - 3 The art of Deconvolving Lunar Images Comet Linear A2 with Jet Sprays 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