Sharpless 261 AKA Sh2-261 aka Lower's Nebula - HaRGB



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


Here is the pure RGB for comparison:


Scope: AP155EDF w Focus Boss II
Camera: Moravian G4 (16803 ccd) w Astrondon Gen II HaLRGB filters
Mount: Paramount MX
Guided w ST-402 and Borg 60mm guidescope
Acquired using TheSkyX
9/9/9 x 10 min RGB
6 x 20 min H-Alpha
All calibration done in PixInsight
RGB and H-Alpha processed separately in PixInsight;
Stars removed from the H-Alpha using StarXTerminator
Stars temporarily removed from RGB then added back.
Ha (starless)+RGB combine in Photoshop CC plus extra clean-up and adjustments.
Lucknow, Ontario
February 2023