NGC 7789 is an open cluster in Cassiopea constellation.
It is a very rich and concentrated cluster, formed by several hundred components and with an apparent diameter of 25’; its distance is estimated to be around 7620 light years.
Its age is quite advanced, estimated at 1.7 billion years or slightly less.
Optic Tecnosky Apo refractor LT 130-910 with Riccardi reducer 0.75x (focal lenght 692mm, f/5.3)
Mount Skywatcher EQ8
Camera Atik 4000 with Starlight Xpress external filter wheel 5 positions
Filters Baader 50mm unmounted RGB
Guiding system Artesky Ultraguide 70mm
Exposure details R 19x300" bin1 -20C
G 19x300" bin1 -20C
B 19x300" bin1 -20C
Total integration 4h45'
Acquisition Voyager, PHD2
Processing Pixinsight 1.8, Photoshop CS5
Location Rescaldina (Italy), home terrace
Date 10/13/14 October 2021