Observation Log - May 10, 2000

Observation Log - May 10, 2000 - Tinton Falls, NJ

NGC4676, (The Mice Galaxies) spiral galaxies in Coma Berenices, magnitude 14, dim 2'.8. This is a composite image combining 7 images totaling 14 minutes of integration from 05/09/00 (10:44 to 11:59 p.m.) with 10 exposures totaling 17 minutes from the morning of the 04/20/00. Thus the total integration time was 33 minutes. Images were all taken using the f/6.3 focal reducer, for an effective f/ratio of f/4. Images were processed with dark frame removal, flat frame, then compositing, flatten background, and finally a contrast stretch.

NGC4559, a galaxy in Coma Berenices, magnitude 9.9, diameter 10'.5. This composite was created from 11 images taken between 10:10 and 10:32 p.m. the evening of the 9th, for a total integration time of 22 minutes. Equipment was the 10" Meade LX200 with an f/6.3 focal reducer producing a focal ratio of f/4. Processing included dark frame subtraction, flat frames, then compositing using MaxIm, then an unsharp mask (kernel low-pass), flatten background, and finally a contrast stretch. This is an additional imaging run on NGC 4559, as the object was photographed on the night of May 7/8 as well (see below.) Here is a composite of both sets of photographs, for an image with 55 minutes of exposure in total. Notice the improvement in the image over either of the component images.

M56, a globular cluster in Lyra, magnitude 8.4, diameter 7', distance 31,000 light years. This composite was created from 17 images taken between 3:43 and 4:03 a.m., for a total integration time of 17 minutes. Equipment was the 10" Meade LX200 with an f/6.3 focal reducer producing a focal ratio of f/4. Processing included dark frame subtraction, flat frames, then compositing using MaxIm, then a Digital Development filter (kernel low-pass), and finally a contrast stretch. Here is another rendition of the same image, this time with a Digital Development filter (FFT, low- pass, mild) to maintain detail in the core.

NGC5427, a galaxy in Virgo, magnitude 11.4, diameter 2'.5. This composite was created from 19 images taken between 1:37 and 2:19 a.m., for a total integration time of 37 minutes. Equipment was the 10" Meade LX200 with an f/6.3 focal reducer producing a focal ratio of f/4. Processing included dark frame subtraction, flat frames, then compositing using MaxIm, then an unsharp mask (FFT, low-pass, hard), a median kernel filter, flatten background, a Maximum Entropy Deconvolution run, and finally a contrast stretch. This image is quite poor, due to focus problems. A better image will certainly be acquired next season.

NGC6992, the Veil Nebula in Cygnus. I had a half hour left before sunrise this morning, so I popped a few frames on NGC 6992, which is part of the Veil Nebula in Cygnus. This image is a composite of 14 frames, with a total integration time of 28 minutes. Frames were taken between 4:08 a.m. and 4:43 a.m., May 10, 2000 using the 10" Meade LX200 with an f/6.3 focal reducer producing a focal ratio of f/4. Camera was the Starlight Xpress MX516. Processing was with MaxIm: dark frames, flats, background removal, compositing, flatten background, and finally a contrast stretch. This one was just for fun, not a serious effort. The seeing was poor last night, particularly from the front yard! Just for grins, here are the same images, but processed without the background removal step. Both have the same amount of contrast stretch at the end, so the difference is due only to the background removal step.

NGC6384, a spiral galaxy in Ophiuchus. This image is a composite of 53 frames, with a total integration time of 67 minutes. Frames were taken over three nights, May 2, May 7, and May10, 2000, using the 10" Meade LX200 with an f/6.3 focal reducer producing a focal ratio of f/4. Processing was with MaxIm: dark frames, flats, compositing, and finally a contrast stretch. This object is magnitude 10.6, with the length of the major axis at 6'.0, yet it was surprisingly difficult to image. The first 27 minutes were taken at Coyle field, and the remaining time was taken from Tinton Falls. The addition of the Tinton Falls images did very little to improve the final image.