by Rex Parker
Several nights before and after the recent opposition of Jupiter were great for telescope observing and imaging the gas giant. I was able to get some decent images from my backyard astro-imaging setup just before Labor Day when I could afford to be sleep-deprived while on vacation from work.
The image above was taken with a CCD camera (SBIG ST10XME with CFW8/RGB filters) and my 5-inch, f8 Takahashi FS128 refractor with 5X Barlow. This arrangement yielded f/40 and approx. 5000 mm FL. Even while using a ~700X 500 pixel subframe at 0.1-0.5 sec per image, it took many hours to acquire the hundreds of individual L,R,G,B frames to find the best “seeing” images to put the LRGB composite together. In a way I guess this turned out to be an advantage since I had to stay out much later than I would have otherwise, and Jupiter reached transit at nearly 4 AM with me still taking frames. The best frames were selected using a subroutine which grades sharpness (from CCDOps). Then they were assembled using MaximDL from single ~0.2 sec exposures for each RGB filter and 60% L (luminance) and combined for the LRGB composite. The S/N was high enough to not need to stack sub-frames.
When I finally did get to sleep I dreamed of life on the gas giant. (Anyone else read the sci-fi novel, The Algebraist by Ian M Banks?)