Rob Hawley's Pages	Almaden Observatory Main Page
Project Overview

Cygnus

In 2016 I imaged a mosaic in the northern part of Cygnus. The area is mapped below.

Map of Mosaic Area

Annotated Image

This reduced size map will allow you to identify the Sharpless and NGC/IC objects in the full image below

Scrollable Image

The actual image is more than 100 Mb (although reduced as a JPEG). This scrollable image will allow you to zoom in for closer examination of the objects in the field. One of the most interesting does not have a Sharpless catalog entry. It is an area in the upper left of the image that is similar to Super Nova reminants like the nearby Veil.

Associated Projects

As mentioned earlier the brighter portions of this image were already the subject of previous narrowband projects.

NGC 7000
SH 108
SH 119

Processing Details

Since this is a monochrome image the processing is much simpler than for a pseudo-color image. No need to do color correction or fix blown out star images.

All images were taken with a Astrodon 3 nm Hydrogen Alpha filter at 900 sec. Notice that unlike previous projects most sections only used 16± exposures. That is because the combination of the 1100AE and active guiding eliminated most of the bad tracking problems I have dealt with for many years. Consequently I am only including enough exposure to use the Winsorized noise technique. I started on another section that finished SH 108 and includes the Crescent Nebula (NGC 6888), but at this point I do not have enough images. Consequently it will have wait until I expand this mosaic.

Number of Exposures of each section
Section	#Images
A26	18
A27	17
A28	15
A32	15
A33	14
A34	13
A37	17
A38	18
A39	16
A40	16

Processing Details

I did a couple of things differently in this mosaic than I did in the past. Using a suggestion from IP4AP I created masks using MLT and did some preliminary noise reduction while the image was still linear. Other than that the image was processed as I would any image

Align and combine each section
Build a reference mosaic using my reference images
Align Separate each section to the reference mosaic
Combine the separately aligned sections using GradientMergeMosaic to create the image
Use Fitsheader to copy the location of the reference image then use the ImageSolver script to determine actual location. A distortion model was also built
MLT for masks then for noise
HT
HDRMT
Curves
MMT
TGV Denoise
Curves

This was the first project I have done that has really made use of my 6 Xenon Processor, 32 Gb Mac Pro. A single project requires 22 Gb of memory.

Copyrights For Photos

(c) 2014-2016 Robert J Hawley Some Rights Reserved.
Except as noted,all work on this site by Robert J. Hawley is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. This permits the non commercial use of the material on this site, either in whole or in part, in other works provided that I am credited for the work.