NGC 5248 - A Spiral Galaxy in Bootes
NGC 5248 - A Spiral Galaxy in Bootes
NGC 5248 - A Spiral Galaxy in Bootes
Also known as Caldwell 45, NGC 5248 is a beautiful spiral galaxy which is a member of the Virgo cluster of galaxies. The galaxy is classified as a star burst galaxy. At 6' x 4' angular size, the galaxy is a challenging target.

In this photo, North is Up. This image is cropped to 42% of the original full frame.

Exposure Details
Lens Celestron C-8 SCT with Celestron focal reducer
Focal Length 1160mm
Focal Ratio f/5.8
Mount Schaefer GEM - 7 1/2 inch Byers gear
Guiding ONAG On-Axis Guider, Lodestar autoguider, PHD Guiding
Camera Canon 450D - Gary Honis modified
Exposure 119 subexposures of 300 seconds each at ISO 1600 - about 10 hours total
Calibration 20 darks, 30 flats, 30 bias
Date May 30 and 31, and June 1, 2013
Temperature 56F on 5/30, 59F on 5/31, 66F on 6/1
SQM Reading 21.4 (Bortle 4) on all 3 nights
Seeing 2 of 5 on 5/30, 4 of 5 on 5/31 and 6/1
Location Pine Mountain Club, California
Software Used Images Plus 5.0 for camera control, IP 5.5 Beta for calibration, stacking, digital development, star shrinking and halo reduction, smoothing and noise reduction, advanced Lucy-Richardson deconvolution, and multiresolution sharpening. Photoshop CS5 used for levels and curves, high pass filter, star shrinking, screen mask invert, lab color, saturation adjustments, selective color, vibrance, match color and lens correction. Gradient Xterminator for gradient removal. Carboni Tools for additional noise reduction, and smoothing. HLVG for additional color correction. Registar for aligning stacks and composites and for color channel alignment. Focus Magic for focus restoration.
Notes I was quite happy with the details I was able to capture in this galaxy. The galaxy has a faint outer halo, and I was also pleased with how well it came out.