Abell 53/PK 40-0.1 is a one-half minute in diameter nice red ring planetary nebula in Aquila. I found several papers giving distances to this nebula. Some were behind paywalls, including the newest. So I'm stuck with older papers about 10 years old saying a distance of about 5500 light-years with a rather large range. Using the 5500 figure it would be about 0.8 light-years across. The central star is only about magnitude 20.8 or 20.9 depending on the source. Other than this I'm not able to find much on this nebula or the field for that matter. It is in the dark rift that passes through Aquila so everything is obscured that lies beyond the dust.

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME