The Polaris Nebula - the IFN throughout Ursa Minor
The Polaris Nebula - the IFN throughout Ursa Minor
The Polaris Nebula - the IFN throughout Ursa Minor
The Polaris Nebula is a very faint section of nebulosity in the apparent direction of Polaris, the North Star. The nebula is listed in the Mandel Wilson catalog of Unexplored Nebulae as MW1 and is an example of the Integrated Flux Nebula. These type of nebulae lie in the outer regions of our galaxy and consist of fine dust particles illuminated by reflecting light from the entire Milky Way Galaxy. These clouds are very subtle and present quite challenging targets to photograph.

This image is centered on the constellation of Ursa Minor, the Little Bear, which is more commonly known as the Little Dipper. Polaris, the bright white star on the left marks the end of the handle of the dipper, while Kochab and Pherkad, the bright yellow and blue stars, respectively, on the right outline the end of the ladle.

In this image, North is to the left.

Exposure Details
Lens 50mm f/1.8 Olympus Zuiko prime lens
Focal Length 50mm
Focal Ratio f/4
 
Mount Schaefer GEM - 7 1/2 inch Byers gear
Guiding Lodestar autoguider via Celestron C-8, PHD Guiding
 
Camera Hutech modified Canon 6D
Exposure 97 subs of 600 sec @ ISO 200 (16+ hours total exposure)
Calibration 30 darks, 30 flats, 30 flat darks, 30 bias
 
Date May 26, 27, 28, 29, and 30, 2014
Temperature 5/26-60F, 5/27-53F, 5/28-53F, 5/29-53F, 5/30-51F
SQM Reading Typically 21.35 to 21.50 (Bortle 4) at zenith, about 21.10 in the direction of this image
Seeing 3/5 on 5/27 and 5/29, 4/5 on 5/26 and 5/28,5/5 on 5/26
Location Pine Mountain Club, California
 
Software Used Images Plus 5.75 for camera control, calibration, and stacking. Images Plus 6.0.5 for ArcSinH stretching and star size reduction. Photoshop CS5 used for levels and curves, screen mask invert, lab color, saturation adjustments, selective color, and match color. Gradient Xterminator for gradient removal. Carboni Tools for additional noise reduction, and smoothing. HLVG for additional color correction. Registar 64 for aligning stacks and luminance calibration. Pixinsight 1.8 for frame adaptation, dynamice background extraction, color calibration, stack merging, histogram transformation, and morphological transformation.
Notes I've imaged a few other sections of Integrated Flux Nebula, and I always find these objects to be both challenging and rewarding. This section of the IFN was even more difficult than the others, since the bulk of the nebulosity is centered around the North Star. This part of the sky is only about 35 degrees high for me. Worse yet, the direction of this image (due North) has me looking straight towards the lights of Bakersfield, a city of about 300,000 only 40 miles from me. As such, this is the brightest part of my sky - not the conditions you want while trying to capture ultra faint nebulae!

This image is the result of my fourth time processing this data. At last, I'm overall pleased with the final result. I tried a number of new techniques in processing this image - some effective and some I clearly need to practice more. Maybe some day I'll try processing a fifth version. But, for now, I'm putting this one to bed!