This is a somewhat unfamiliar view of the familiar duo of M81 and M82, here including some of the integrated flux nebula (IFN) that lies in their direction.  IFNs were first recorded in the 1950s in images of the Palomar Sky Survey.  According to Wikipedia, "the term was coined by Steve Mandel who defined them as 'high galactic latitude nebulae that are illuminated not by a single star (as most nebula in the plane of the Galaxy are) but by the energy from the integrated flux of all the stars in the Milky Way. As a result, these nebulae are incredibly faint, taking hours of exposure to capture. These nebulae clouds, an important component of the interstellar medium, are composed of dust particles, hydrogen and carbon monoxide and other elements.'" 

I processed this entirely in PixInsight, starting with WBPP just for calibration and debayering.  I then ran Subframe Selector to select frames manually, and then proceeded with registration, integration and 1x drizzle.  I did not run Local Normalization for fear that it would alter or remove IFN.  I used PI's new Gradient Correction tool, gingerly for the same reason.  I applied different GC settings to multiple copies of the integrated image and found the IFN looked best when I used the Simplified Model and reduced the Low Threshold and Low Tolerance. From there, I followed my usual linear workflow of BlurXterminator correct only, SPCC, BlurXterminator, NoiseXterminator and StarXterminator.  I stretched with Generalized Hyperbolic Stretch, with two aims: to bring out the IFN and at the same time to minimize saturated pixels in the galaxies.  In non-linear, I used many range masks, some with very small ranges between the lower and upper limits, to bring up the IFN, darken the small amount of true background sky, and manage brightness and contrast in the galaxies.  This is actually my fifth end-to-end attempt at processing this data.  Of the first four, two bring out the IFN strongly but leave the galaxies look artificial, and two have good-looking galaxies with just wisps of IFN.

This image comes from data captured on just one night at the Chiricahua Astronomy Complex in Pearce, Arizona, a dark-sky site about 90 minutes from Tucson.  It was my first visit to CAC and I thought I'd target something that would be hard or impossible to capture from my Bortle 5 backyard in Tucson. There was rain at CAC on-and-off until 5 pm the day I visited, and that left the dew point high.  I rejected the last hour of my images due to high FWHM, presumably caused by dew, though the lens and scope were clear when I checked on the rig at dawn.  That left me with only 80 good subframes, and in my view the IFN needs more integration time or a much faster optical system to do it justice.  I hope to gather more data on this target at CAC again soon.