From GalaxyMap:

The HII region Sh 2-261 is often called Lower's nebula because it appears on a photographic plate taken by the father-and-son team of Harold and Charles Lower in 1939.

The Lowers were amateur astronomers, accomplished telescope makers and pioneering astrophotographers from San Diego, California. Harold Lower published a pamphlet in 1939 describing an 8 inch Schmidt camera that he and his son had constructed several years previously. He notes that the camera has been especially useful in photographing what are now called HII regions:

Another field which we have found interesting is searching for diffuse galactic nebulae which photograph strongly by red light. By the use of red-sensitive film and a deep red filter we have been able to photograph a number of nebulae which are exceedingly faint on blue-sensitive negatives.

[I think you can use O-III here, but there was little Blue on the RGB image and a lot of Red-JY]

Appears to be associated with the O7.5V star HD 41997.

HD 41997 is a runaway star.

BFS incorrectly lists Sh 2-261 as a supernova remnant.

There are several distance estimates available for Sh 2-261 / HD 41997. If the further distances are correct, Sh 2-261 is likely part of the Gemini molecular clouds in the Perseus arm. If the closer 1000 pc distance is correct, then it appears to be part of the Orion spur.

GENERAL NOTE ON SHARPLESS2 OBJECTS>>>>>>>>>>>>>

I have been on a project for several years now to image all the Sharpless2 Objects that I can see from my location near San Francisco. I chose these because they are visible in light polluted areas. These objects generally represent left over Hydrogen along the edge of the Milky Way that has gotten molded into interesting shapes.

There are 313 Sh2 objects and those below 70 and above 283 are generally too low on the horizon for me to image... this leaves me 213 that are feasible... and I have imaged all of these but 24. 13 of these are too big for my system. So 11 to go.

Many were taken with my old Tak 180 ED, which had a wide field of view, but was replaced with my Stellarvue 130, which is more narrow field.

This is my collection:

Sharpless2

Please note there is also a Sharpless2 Group with now more than 1000 examples.

Hope you enjoy these obscure but interesting objects...