DEEP SKY OBJECTS

   Located outside our solar system, often invisible to the naked eye, and require long-exposure photography:

• Nebulae: Interstellar clouds of dust and gas, such as emission, reflection, or dark nebulae within the Milky Way Galaxy;
• Galaxies: Vast systems of stars, gas, and dust outside the Milky Way Galaxy;
• Star Clusters: Dense groupings of stars, including open clusters and globular clusters within the Milky Way Galaxy.  

   INSPIRATION

• Processing the images has been guided by several people, including (in alphabetical order), but not restricted to: ‘Paulyman Astro’ (videos), Adam Block (videos), Charles Bracken (book), Juan Conejero( Pleiades Astrophoto S.L, Pixinsight videos and reference documentation), Frankling Marik (Seti Astro, Website), Tony deNardo (Hidden Light Photography, Website), and Chris Woodhouse (book). Needless to say, they would each have processed better images than those published by CNStudios.org.
• There are many varied approaches to processing astrophotographic images of deep sky objects, often resulting in quite different outcomes. My broad sequenced approach is as follows:

   1.1 PIXINSIGHT

• Weighted Batch Pre-processing is done separately for each narrowband image, using appropriate lights, light darks, flats and flat darks, with drizzle applied.
• Each drizzled master image is deconvoluted, noise reduced and, if needed, gradient corrected.
• The images are star aligned with Ha image as reference and dynamic crop is applied if needed.
• Images are corrected with HLP Astro Image Primer and then integrated to form a luminance image, which is then saved starless, having extracted the stars.
• The monochrome images are combined with pixel maths, either with Hubble palette or the palette of Charles Bracken.
• Generalized Hyperbolic Stetch and Curves Transformation are then applied. 
• The starless luminance image, following stretching, is then combined with the stretched colour image.
• The stars from the luminance image, after stretching, are then put back into the colour image with HLP_starsback.
• The resulting file is saved as a 16-bit TIFF file.

   1.2 TOPAZ STUDIO

• The TIFF file is adjusted with denoise, sharpen and enlarged with gigapixel.

   1.3 ADOBE PHOTOSHOP

• The TIFF file is adjusted as required, sometimes expanding with firefly, and saved with standard A3+ size, landscape, or, very occasionally, portrait.    

   1.4 SAVING FILES

• The Pixinsight Master folder (other folders are deleted to save space) is saved on the working computer with the folder name [classification of the image and the date of aquisition] for further work and publishing as needed. Copies are saved to a portable SanDisk extreme drive (to move between locations), G-RAID in one location and internet-accessible NAS storage device in a separate location.