In May 2013 I photographed M16, acquiring 21x 180sec exposure images to total 63min. I initially calibrated and stacked in Nebulosity, and edited in Photoshop. Since end 2013 I’ve moved over to processing in PixInsight, and have been wanting to reprocess some of my previous images.
Acquiring in Nebulosity
Unfortunately all the images I acquired on my May 2013 Sutherland trip were auto-stretched by Nebulosity. Unbeknown to me I wasn’t shooting true RAW, and Nebulosity was applying an auto-stretch to my images, diminishing the quality of data. I only noticed this when bringing data into PixInsight, having the FITS already in a non-linear state directly after being integrated. So, some advice; Ensure that you set your “Acquisition Mode” in Nebulosity to RAW. It’ll go a long way in preserving quality. (Although you’ll have to debayer)
Processing in PixInsight
The colour balance is much better than the original image. Although I don’t have as much of the surrounding area’s nebulosity showing, I prefer this rather than the reddish blotchy appearance of the initial image. I also used a process called “Morphological Transformation” that helps reduce stars. With this area being filled with so many stars, it really helped bring out the detail in the nebula – by reducing the star field.
I used this tutorial by Rogelio Bernal Andreo
Since the quality of data was poor to begin with I didn’t spend too long on re-processing this. Next try will be with better data; M31!
Looking for some PixInsight tutorials? Sean Curry’s site www.drakevisual.com has some interesting links