You're perhaps wondering why I'm mentioning M16 in the title but showing a completely different object in the  image...

Popular targets such as Messier 16 draw so much attention that surrounding sky can be neglected, so let's explore M16's "backyard".

The sky around M16 checks all the boxes. It's a complex patch of sky for a deep and relatively widefield opportunity for a full frame mosaic using the RASA 11: taking advantage of its fast optics to reach well into the dust over a couple of nights.  I enjoy seeing into the dust, and how everything is connected.

I present a SHO 2-panel mosaic as the original upload, and crops therefrom,  using data from an ASI6200MM-Pro and processed at 2x drizzle scale. It's intentionally stretched to reveal details in the dust lanes. The actual 5 GB 32-bit RGB PI .xisf file is 18,480 x 22,900 pixels, about 400 megapixels. Will that fly? Let's move fast and break things!

Unfortunately this resolution, even as a compressed jpeg, broke the AB machine. For AB to accept the upload I downscaled it to 80% its original size,  but it holds up pretty well at 18.3k x 14.8k. There's a lot to see by zooming in and wandering about. 

The additional crops are full scale. AB's thumbnailer also crashed when I ran it on the full mosaic. To get around this, I selected a rarely posted cropped scene around NGC6604 including Sh2-54, and LBN's 70, 71,and 72. I thumbnailed that, and called it the final revision.  I hope you enjoy it, along with the gallery of other viewpoints along the trail! 

The annotated full mosaic page is working fine: https://www.astrobin.com/wd3e6o/0/

New! The 270 megapixel mosaic now also in ForaxX dynamic palette in Revision M, with M16 close-up in rev. N.

Yup, there's plenty to enjoy in the backyard! 

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I have other reasons for having done this project. The wide mosaic at full resolution is a resource, a personal survey image if you will, of this part of the sky taken with my own gear under my own typical sky. This becomes a great planning tool  to revisit anything in this field later for deeper exposure time and perhaps with another optic like my C9.25HD for a better view and result. I can measure this image's SNR, knowing exactly how it was imaged,  and better predict what total time I should use for any other optical f-ratios with differing sky SQM, when I later wish to image any of these targets individually. But even with just this mosaic, I can refine these crops with CurvesTransformation etc. in PI to create versions in styles that suit each crop individually.

Astrobin's etiquette rules forbid creating separate pages for these crops, since they all derive from a single dataset. To honor that rule, I've done things this way, using the Revisions feature on AB to create a gallery of astronomical treats.