Observation Log - May 6, 2002

Observation Log - May 6, 2002 - Tinton Falls, NJ

Tonight's configuration: Dew shield/Crayford focuser/f3.3 focal reducer/T- adapter/MX516 camera, upside-down with no filters. Temperature at 3:00 am was 46F. Had very slight dew during the night, but nothing on the optics. Tonight was the first use of the new USB interface between the camera and the computer. The old one had failed and was replaced for free by Adirondack Video Astronomy.

Tonight's first image is NGC 3646 a galaxy in Leo. This object is magnitude 11.1, and measures 3.9' x 2.2'. Surface brightness is 13.5 mags/sq. arcmin, and the distance is given as 180 million lightyears. This object is a composite of 55 one-minute images, processed using MaxIm CCD. All images were taken between 9:25 and 10:55 pm the evening of the 5th. After calibration (darks/flats/bias) the images were combined, then resized to double the image scale. The image was cropped, rotated 180 degrees, and then processed with a Digital Development filter (kernel, low-pass, more). I used an FFT filter (low-pass, mild) and an unsharp mask (FFT, low-pass, hard) then did a gradient removal and finished with a contrast stretch and a resizing back to normal. Here is the version at double the image scale.

Next is M64 a galaxy in Coma Berenices, magnitude 8.5, 10.3' x 5.0'. Surface brightness is 11.7 mags/sq. arcmin. Distance to this galaxy is given as 12 million lightyears, and it extends for 35,000 lightyears. This image is a composite of 77 one-minute images. All images were taken between 11:02 and 12:50 am the morning of the 6th. After calibration the images were combined, then resized to double the image scale. The image was cropped, rotated 180 degrees, and then processed with a Digital Development filter (FFT, low-pass, hard). The image was finished with a contrast stretch and a resizing back to normal. Here is the version at double the image scale. Here are two versions using the AIP MED algorithm to sharpen things up a bit... little M64, and big M64.

Here is NGC6339 a galaxy in Hercules, magnitude 12.7, 2.9' x 1.7'. Surface brightness is 15.3 mags/sq. arcmin. This photo is a composite of 36 one-minute images. All images were taken between 12:58 and 1:41 am the morning of the 6th. After calibration the images were combined, then resized to double the image scale. The image was cropped, rotated 180 degrees, and processed to flatten the background and remove a gradient. Then I applied a Digital Development filter (FFT, low-pass, hard). The image was finished with a contrast stretch and resized back to normal. Here is the version at double the image scale.

This is NGC5945 a galaxy in Bootes, magnitude 12.8, 2.1' x 2.0'. Surface brightness is 15.6 mags/sq. arcmin. This photo is a composite of 45 one-minute images. All images were taken between 2:00 and 3:04 am the morning of the 6th. After calibration the images were combined, then resized to double the image scale. The image was cropped, rotated 180 degrees, and processed to flatten the background and remove a gradient. Then I applied a Digital Development filter (FFT, low-pass, mild) and an FFT filter (low-pass, medium). The image was finished with a contrast stretch and resized back to normal. Here is the version at double the image scale.

The final image of the night was NGC6389 a galaxy in Hercules, magnitude 12.1, 2.8' x 1.9'. Surface brightness is 13.8 mags/sq. arcmin. The distance to this galaxy is 140 million lightyears. This photo is a composite of 43 one-minute images. All images were taken between 3:08 and 4:28 am the morning of the 6th. After calibration the images were combined, then resized to double the image scale. The image was cropped, rotated 180 degrees. Then I applied a Digital Development filter (FFT, low-pass, hard)and finished with a contrast stretch and resizing back to normal. Here is the version at double the image scale.