Observation Log - July 23, 2000 - Tinton Falls, NJ

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NGC7635, the Bubble Nebula, a bright nebula in Cassiopeia, diameter 15'. This used the f/6.3 focal reducer and the Homeyer color filter wheel was in place, giving an effective focal ratio of f/4. The frames were shot between 02:37 a.m. and 04:29 a.m. on the morning of the 23rd. The composite used 40 exposures for a total integration time of 80 minutes. All images were processed with dark frame subtraction and flat frames, then compositing, Digital Development (Kernel, low-pass), unsharp mask (Kernel, low-pass), a Kernel median filter, and finally a contrast stretch. Here is a lower contrast version of this image which shows more detail at the center of the bubble.

IC 5146, the Cocoon Nebula, an open cluster and nebula in Cygnus, magnitude 10.0, diameter 9'. This effort used the f/6.3 focal reducer and the Homeyer color filter wheel was in place, giving an effective focal ratio of f/4. The frames were shot between 01:11 a.m. and 01:55 a.m. on the morning of the 23rd. The composite required 15 exposures for a total integration time of 30 minutes. All images were processed with dark frame subtraction and flat frames, then compositing, Digital Development (Kernel, low-pass), unsharp mask (Kernel, low-pass), a Kernel median filter, then an FFT filter (low-pass, mild), and finally a contrast stretch. The Cocoon Nebula is both a reflection and an emission type, and shows distinct dust lanes, and darker obscuring regions around the outside edges.

M52, The Scorpion, an open cluster in Cassiopeia, magnitude 6.9, diameter 16', distance 5,100 light years. The f/6.3 focal reducer and the Homeyer color filter wheel were in place, giving an effective focal ratio of f/4 on the Meade 10" LX200. The frames were shot between 02:01 a.m. and 02:18 a.m. on the morning of the 23rd. The composite used 8 exposures for a total integration time of 16 minutes. All images were processed with dark frame subtraction and flat frames, then compositing, Digital Development (Kernel, low-pass), and finally a contrast stretch.

M39, an open cluster in Cygnus, magnitude 4.6, diameter 30', distance 950 light years. This photo shows only the inner core of this very large cluster. The f/6.3 focal reducer and the Homeyer color filter wheel were in place, giving an effective focal ratio of f/4 on the Meade 10" LX200. The frames were shot between 12:49 a.m. and 01:06 a.m. on the morning of the 23rd. The composite used 8 exposures for a total integration time of 15 minutes. All images were processed with dark frame subtraction and flat frames, then compositing, Digital Development (Kernel, low-pass), and finally a contrast stretch.

NGC6755, an open cluster in Aquila, magnitude 7.5, diameter 15'. This effort used the f/6.3 focal reducer and the Homeyer color filter wheel was in place, giving an effective focal ratio of f/4. The frames were shot between 12:21 a.m. and 12:40 a.m. on the morning of the 23rd. The composite required 9 exposures for a total integration time of 18 minutes. All images were processed with dark frame subtraction and flat frames, then compositing, Digital Development (FFT, low-pass, mild), then flatten background and finally a contrast stretch. NGC 6755 is composed of about 100 stars with the brightest at about magnitude 10.2.