NGC 6366 is a fairly faint (9.2 mag) ans very weakly concentrated globular cluster in the constellation of Ophiuchus. Its apparent size is smaller than 6' and it's real distance is about 12.000 light years. Its a very metal rich cluster, which causes its yellowish colour. Additive to this, there is a very high interstellar extinction.
In an 8 inch instrument you can barely detect it as a pale grey spot in the neighbourhood of the blue 4,5 mag star SAO 141665.
RA: 17h 27m 42s
Dekl.: -05° 05′ 00"
L(synth)RGB,RGB=6x1200s each, total time:6.0h, Seeing: 0.9-1.2", 80cm f/7 AstroOptik-Keller corrected Cassegrain, FLI Proline 16803,Baader-RGB-filters, Promt7 CTIO/UNC Chile, remote controlled
Image processing: Bernd Flach-Wilken
here you can take a look at the HST picture,that shows the very center of this globular cluster