I wanted to image Planetary Nebula M 2-52 with my 10" Meade ACF, but noticed that I would get M 2-51 with half the focal length. It is only 13 arcseconds large but interestingly shaped.
I have therefore targeted both of them with the Esprit 150 APO.
I gathered the data in three nights around August full moon (the second exactly at full moon on the day of the partial lunar eclipse), the last two of which were "blessed" with thin clouds.
In two nights I had a lot of tracking errors (stars were moving around in rectangles), which I did not notice then. When I was on my rooftop terrace for a check, everything looked OK. I attribute the tracking error to the fact that there was a second star in the image section selected for guiding. It was clearly weaker than the guidestar, but probably seeing and other factors gave this second star a brighter center than the guidestar in some guide exposures. I used some of the affected images anyway, because otherwise there would have been too little exposure time left.
Taken from Berlin with an Esprit 150 APO on an AZ-EQ6 mount, ASI1600MMC camera, 64x5 minutes ha, 50x5 minutes OIII, everything at Unity Gain.
Image scale is 0.75"/pixel.
At the top left is the small M2-51, which has an unusual tail to the right. M2-51 is hopefully easier to find in the right half of the picture.
As the image is too large for spacebanter.com I post a link:
http://ccd-astronomy.de/temp12/Minko...OIII%29gut.jpg
I have also attached an inverted and cut-to-size Ha-version where both nebulae are nearer to each other, just to get them on a full HD screen.