Observation Log - July 21, 2000 - Tinton Falls, NJ

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M22, a globular cluster in Sagittarius, magnitude 5.2, diameter 33', distance 10,100 light years. This image was made using the f/6.3 focal reducer and the Homeyer color filter wheel, giving an effective focal ratio of f/4. This RGB composite was created from 15 images with a total integration time of 15 minutes, 5 minutes in each color channel. All images were taken between 11:43 and 12:02 a.m. the night of July 20/21. All images were processed with dark frame subtraction and flat frames, then compositing each channel individually. Each color image was processed with Digital Development (Kernel, low-pass), then color compositing and finally a contrast stretch. Here is the same image resampled to be 33% larger to show a little more detail.

NGC7331, a galaxy in Pegasus, magnitude 9.5, dimensions 11'.4 x 4'.0. For this image I used the f/6.3 focal reducer and the Homeyer color filter wheel was in place, giving an effective focal ratio of f/4. This composite was created from 51 images with a total integration time of 80 minutes. All images were taken between 12:13 and 03:14 a.m. the morning of July 21st. All images were processed with dark frame subtraction and flat frames, then compositing, unsharp mask (FFT, low-pass, medium), Digital Development (Kernel, low-pass), flatten background, a kernel filter (low-pass), and finally a contrast stretch. Here is a map of the galaxies that are found in this photo. Here are some stats on the companion galaxies: NGC7340, mag 13.7, 0'.9 x 0'.6; NGC7337, mag 14.4, 1'.2 x 1'.0; NGC7335, mag 13.4, 1'.4 x 0'.6. And here is an RGB version of this image, with 18 minutes in red and green, and 22 minutes in blue. Color frames were taken between 01:50 and 03:14 am. The color channels were each processed independently, then composited and color combined, then a Digital Development (kernel, low-pass), and finally a contrast stretch.

NGC7479, a galaxy in Pegasus, magnitude 11.0, diameter 4'.1. For this image I used the f/6.3 focal reducer and the Homeyer color filter wheel was in place, giving an effective focal ratio of f/4. This composite was created from 50 images with a total integration time of 66 minutes. All images were taken between 03:26 and 04:47 a.m. the morning of July 21st. All images were processed with dark frame subtraction and flat frames, then compositing, unsharp mask (FFT, low- pass, medium), Digital Development (Kernel, low-pass), flatten background, a kernel filter (low-pass), and finally a contrast stretch.

NGC6905, a planetary nebula in Delphinus, magnitude 12.0, diameter 1'.7. This image used the f/6.3 focal reducer and the Homeyer color filter wheel, giving an effective focal ratio of f/4. This LRGB composite was created from a luminance component that included 13 1-minute exposures. The red, green, and blue components were each formed from 7 1-minute exposures. All images were processed with dark frame subtraction and flat frames, then each channel was composited separately. The luminance channel was processed with Digital Development (FFT, low-pass, mild) and an unsharp mask (FFT, low-pass, mild.) The final image was color combined, re-aligned, color balanced, color smoothed (FFT, low-pass, mild), and finally contrast adjusted. All images were taken between 09:52 p.m. and 10:40 p.m. the evening of July 20, 2000. Here is another version of the same image, resampled to be about 50% larger. Here's a white- light version of the original image of NGC6905 that shows perhaps a bit more detail. And finally, here's a high-contrast version of the white-light image. Notice on this version, the fringe material that becomes visible toward the top and bottom of the object. Also, I seem to see a dark "rift" in the surrounding star field that starts on the right side of NGC6905 and extends toward the upper-right corner of the frame. Might this be a dark cloud, or just a random lack of stars in the field?

M20, The Trifid Nebula in Sagittarius, magnitude 6.3, dimensions 20' x 20', distance is 5,000 light years. 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. This LRGB composite was the result of two nights of photography. The white (Luminance) component was shot on July 8-9 (11:59 pm through 12:07 am), and included 7 1-minute exposures. The Red, Green and Blue components were taken on July 20 (10:55 through 11:24 p.m.). All images were processed with dark frame subtraction and flat frames, then each channel was composited separately. The final image was color combined, re-aligned, color balanced, color smoothed (kernel, low-pass), and finally contrast adjusted.