I finally got my first stacked astrophotograph that contains nebulosity! After months/years of Murphy's law creating a sort of Drake equation for the probability of getting a half decent astrophoto being similar to the experience of astronomers currently looking for earth-like planets, there was a clear moonless night at the weekend, x my mount was aligned and doing goto and perfect tracking, x my equipment balanced, x my DSLR camera properly focused with live view zoomed in at the eyepiece of the refractor, x Magic Lantern properly set, x camera batteries didn't die x dew didn't come down x I didn't kick the tripod x and 50 x 15 second RAW light images and some dark frames saved x stacked at first try with Astro pixel processor!
My reaching this basic stage is in no small part due to the help I have received on this website, so many thanks to all who have answered my posts over the years. (I realize, my alignment is not that great, as I have still not cracked the precise balancing and precise polar alignment problem to enable exposures longer than 15 sec through the refractor, but at least it was good enough to get to this stage! ...and also, I need to take white flats in daylight to improve the picture further, which I could still do).
However, since I put the DSLR directly on to the 93mm f5.5 triple achromat refractor, I think the image is upside down and backwards. This makes it hard to compare with a star atlas (I have gone to the free Tri-Atlas star charts on line, since the FOV seems to be about 2x2 degrees so very small on my star atlas) to see whether I have actually photographed where I thought I had. The photo is near Sadr in Cygnus. I recall that Sadr was to the right of centre in the DSLR live view, but in the processed photo it is to the left. Which makes me wonder if the software already flipped it - but it can't 'know' whether flipping is necessary or not since I might have been using simply a telephoto lens.
Also, the file is a 253Mb FITS file. I am not sure how to get it out of astropixel processor in a more friendly format ...? It doesn't seem to have a save as JPG option...