M71 is a controversial object in the Sagitta constellation: globular or open cluster?
Until 1970 it was considered a particularly concentrated open cluster but various clues suggest that we could be faced with a poorly concentrated globular cluster and in fact today this seems to be the prevailing opinion of astronomers.
M71 is located at a distance of about 12,000 light years from Earth and has a real extension of only 27 light years, very few for a globular cluster; its apparent diameter is 7.2’.
Optic GSO RC12 Truss - Aperture 304mm, focal lenght 2432mm, f/8
Mount 10Micron GM2000 HPSII
Camera Moravian G3-16200 with external filter wheel 7 positions
Filters Astrodon Gen2 E-Serie Tru-Balance 50mm unmounted RGB
Guiding system OAG Moravian M68 with guide camera Moravian G1-0301
Exposure details R 12x300" bin2 -20C
G 15x300" bin2 -20C
B 10x300" bin2 -20C
Total integration 3h5'
Acquisition Voyager, PHD2
Processing Pixinsight 1.8, Photoshop CS5
Location Promiod (Aosta Valley, Italy), own remote observatory
Date 29 August/1 September 2021