I have not imaged both the North America Nebula (NGC 7000) and the Pelican Nebula (IC 5070) in the same before so I figured this would be an excellent object to do some more testing. I wanted to compare the Baader Neodymium (Moon & Skyglow) Filter with the IDAS NBZ Filter so there will be another image using the NBZ once the weather permits and I image it. The filters are quite different in what they are designed for and light they filter out so it is not a comparison which is better but more about what each filter can do.

I am very impressed with this Skyglow Filter especially since it was done when the moon was up. There were some gradients but nothing the flats could not handle. There is very good dynamic range across the both nebulae, more than was expected. I like how the outer sharp dense red portions grade into the white inner regions. The Wall, 'outer red portion of Mexico' is very distinctive as are some of the other red tendrils on the North America and edge of the Pelican.  On the center right side of there is a small white cloud which is actually a reflection nebula, IC 5076, that I never new was there.Another interesting thing about this image is that it is only 1.5 hours of exposure (45 x 120s). I did not go to longer exposures since it was a broadband image and the moon was out but despite that it came out rather well, much better than I was expecting. I used Bill Blanshan's star reduction - my new favorite star reduction method to reduce the heavily star-packed region as this sits in the Milky Way plane.

Lastly, I did not create flats for this image at first and wound up with the heavy gradients. You can see where the step-down rings exacerbate the gradient issue (Fig. 2). There are ways to fix this in post processing using heavy careful curve adjustments and/or synthetic flats which is what I did for the previous M16-M17 image. However, I decided to make a set of flats even though I imaged other objects with other filters in between - it worked as the gradients were removed or lessoned (Fig. 3). I show this because I see a lot of posts saying that it is useless to do flats after moving the imaging train. The original function of a flat field is to get rid of the uneven gradients from the background. They do have another benefit in that they can remove dust bunnies and other artifacts. The 'dust bunny' removal may not happen if you do what I did and take the flats weeks later but the gradients were certainly reduced. This made processing much much easier which is the whole point of flats. Long and short of it, if you forget or are unable to take flats at the optimal time, go ahead and try at a later date - the worst that can happen is it does not work...