Abell 1185 is a galaxy cluster located in the south of the constellation Ursa Major, about 430 million light-years away from Earth. Most interesting part of the cluster is Arp 105 (with common name the Guitar", which can be  easily found in the picture ), formed by interacting galaxies NGC 3561 and 3561A and a tail-like tidal structure (guitar neck), stretched in northern direction from NGC3561A.  The small tidal dwarf galaxy just south of NGC 3561 is known as Ambartsumian’s Knot..
There are many (~150) well resolved galaxies in the field and also several rather distant (about ten times more than Abell 1185) galaxy clusters, e.g. that  NE from the guitar or to the right from the center. There all the reddish "stars" are in fact distant galaxies with recessional velocities ~ 100000 km/s.
In the background you can also find many quasars and as an example I  marked with an arrow at least one bright quasar near the bottom edge  center, with redshift z=3.21 and light travel time ~ 11.7 billion light years.

Optics:       NoName Newton 192/800
                   +GPU c.c.
Camera:    Atik One 6
Filters:        LRGB Baader
Mount:      SW AZEQ-5
Guider:       Lacerta MGEN
Exposure:  545 min. (L)
                    14x5 min. (R, G, B each), bin 2x2
Software:  PixInsight, Photoshop
 11.4.2020

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