1 pc = 206264.806... astronomical units (AU) = (3.08567758...)*10**16 m = 3.26156377... light-years (ly) ≅ 3.26 ly.
Therefore HCG 87 is about 400 Mly away.
The points are part of the diffraction patterns of the brighest stars. They show up because of strong overexposure. The brightest stars are much brighter than the other astronomical objects in the image.
There are 4 points for each diffraction pattern because the CCD camera is held in front of the primary mirror by 4 arms. The 4 arms give a 4-fold symmetry that communicates itself to the diffraction patterns.
Galaxies are actually faint by comparison to bright foreground stars. So to image the galaxies well, you ineluctably overexpose the bright foreground stars.
In enhanced true-color images, the spiral arms are a complex mix of blue (from hot young OB stars), pink (from H II regions emitting the atomic hydrogen line Hα), and brown/black (from obscuration by interstellar dust).
Some images though are clearly false color.
The galactic halos of spirals are faint and often have populations of globular clusters.
Seen face-on or obliquely, spirals are easily recognized.
Seen edge-on, they can still be easily recognized from the colors of the spiral arms even if the spiral arms CANNOT be seen as spirals themselves.
The are just spherical or elliptical blobs that in true color are almost always just yellow with the brightness increasing toward the center.
Ellipticals have little interstellar dust and little star formation in the modern observable universe.
This accounts for their yellow color. They have NO or very few blue hot young OB stars and contain mainly older older Population I stars and Population II stars which, as aforesaid, are yellow to red in color.
Actually, there are NO ellipticals in HCG 87, but lenticular (S0) galaxies (like HGC 87b) look a lot like ellipticals since they have no spiral arms. HGC 87b, in particular, looks like an elliptical to casual inspection, and so can represent ellipticals.
For spiral galaxies, we can infer to some degree there appearance from other orientations because their galaxy types can be recognized independent of orientation.
For elliptical galaxies, situation is a bit harder because their 3-dimensional shapes CANNOT easily be inferred from their 2-dimensional projections on the sky.
Yours truly thinks of galaxies as constituting a giant mobile in space---but one we can only see from point of view---our Earth.