Hickson 61 is a "galaxy group" with four members. But only theoretically, because if you look at the distances you find out that only NGC 4169, 4174 and 4175 (the three white galaxies) have a similar escape velocity and therefore distance, namely between 169 million and 180 million light years. NGC 4173, the largest galaxy of the group, is only 50 million light years away.

On the right side of the image we find three more NGC galaxies, 4131, 4132 and 4134. They have very similar radial velocities as NGC 4169 and Co, around 3600 to 4000 km/s, which again gives a similar distance.
Furthermore we see a myriad of galaxies in the background, partly scattered, partly in clusters like Abell 1496 on the far left or at the very bottom [RRB2014] RM... Their predominantly reddish color comes simply from redshift. Here you can also calculate the "distances" by looking at the redshift "z". For the mentioned [RRb2014] RM.... galaxy cluster, for example, z=0.39730. The "lookback time" for this object is 4.427 billion years, which means that this time has elapsed since the object emitted the light received today. However, this number no longer corresponds to the current distance (this is greater), since the universe has expanded during these 4.427 billion years and the objects have therefore moved away from each other. On such scales therefore "distance data" are no longer really purposeful. 
In the upper right corner we find another interesting object - 2MASS...., an "AGN - active galaxy nucleus". This is a galaxy with a very active nucleus, and it appears green to us. Green doesn't exist at all, we need SCNR or something like that for the processing one would think - but also here simply the redshift might play a big role. An active galaxy normally forms many stars, which are hot in their youth phase and therefore blue. If we shift blue a bit towards red in the spectrum, we end up in the middle of the green range - the galaxy is imaged green.