Object name: NGC6100
NGC 6100 is a ring galaxy in eastern Serpens Caput just about on the celestial equator that is about 230 million light-years from our galaxy and 110,000 light-years across. It was discovered by Lewis Swift on July 3, 1886. He's likely more famous to amateur astronomers for his shared discovery of comet Swift-Tuttle that's responsible for the Perseid Meteor Shower each August. NGC 6100 has both an outer blue ring and an inner pseudo-ring. The area between these came out quite red in my image which surprised me. Oddly the Sloan image shows it more a muddy brown color. I'm not sure why the difference though Sloan picks up 4 bands beyond our visual range that often skews its color. A likely background galaxy is seen through the outer ring to the northeast (upper left). NED shows nothing at its position, another surprise. It's clearly a reddish galaxy that didn't make it into any catalog NED carries.