- Galaxies of the Arp Catalogue (And) -

And (4) Cep (3) CVn (5) Lep (1) Peg (11) Tri (1)
Ari (3) Cet (1) Dra (1) LMi (4) Per (1) UMa (17)
Boo (1) Cnc (1) Gem (1) Lyn (2) Psc (5) UMi (1)
Cam (3) Com (3) Leo (10) Ori (1) Ser (2) Vir (6)

Arp 113 (GLXGRP)

Image source: DSS II (blue) - 6×6'
Name: Arp113, VV166, Holm6
Constellation: And
Coordinates: 00h18m23.30s / +30°03'40.00"

Group Members:
NGC67 (PGC1185) 14m2 0.4x0.3'
NGC68 (UGC170, H5.16) 13m2 1.2x1.1' (90°)
NGC69 (PGC1191) 14m7 0.9x0.8'
NGC70 (IC1539, UGC174) 13m5 2.1x1.7' (5°)
NGC71 (UGC173) 13m3 1.7x1.3' (90°)
NGC72 (UGC176) 13m8 1.4x1.1' (85°)
80mm f/6.25, 62x, Bortle 3, SQM-L 21.3

120mm f/5, 100x, Bortle 3, SQM-L 21.3
I only classified this group as moderately difficult, because I could see a diffuse, roundish brightening near faint field stars with averted vision without any problems. I'm pretty sure, that this is NGC68 as brightest member of the group.

8" f/6, 171x, Bortle 3, NELM 6.4
Overall difficult group with 8 inch, which is embedded between faint field stars. NGC68 (brightest western) is brightest member and appeared at 171x roundish with slightly brighter center, held with averted vision. NGC71 (southeastern of NGC68) was glimpsed as roundish, diffuse brightening. NGC70 (northeastern of NGC68) I tried without any success.

12.5" f/4.5, 205x, Bortle 3, SQM-L 21.3
NGC68: Round, less condensed. Brightest and most obvious galaxy of the group.

NGC70: Appeared very diffuse between two faint field stars. Shape hardly perceptible.

NGC71: Well visible with averted vision as compact brightening.

NGC72: Compact, slightly oval.

Arp 145 (GLX)

Image source: DSS II (blue) - 5×5'
Name: UGC1840, Arp145
Type: GLX
Constellation: And
Coordinates: 02h23m11.42s / +41°22'04.77"
Brightness / Size: 13m4 / 1.5x1.3'
Arp145 actually consists of two galaxies: The brighter PGC9062 (=UGC1840) and the much fainter PGC9060 (v17.8m), which is located in the southwestern part of the "donut".

8" f/6, 200x, Bortle 4
Small, round, slightly darkening toward the edge. Faint star pair nearby. The "donut" (that's no image artifact!) needs more aperture for sure.
Hint: Galaxy located less than 5' from a bright 5.8m star. I recommend an eyepiece with narrow field of view and less internal reflections! A 6mm ortho worked fine for me :-)

Arp 168 (GLX)

Image source: DSS II (blue) - 9×9'
Name: M32, NGC221, UGC452, Arp168
Group: Local Group
Type: GLX
Constellation: And
Coordinates: 00h42m41.83s / +40°51'54.61"
Brightness / Size: 8m1 / 8.5x6.5'
B 40mm, 8x, Bortle 4, NELM 6.1, SQM-L 21.1
Relatively well seen with direct vision, but nearly stellar.

80mm f/6.25, 25x, Bortle 6
Very bright and compact. Can be confused with a star. At higher magnification clearly extended.

8" f/6, 37x, Bortle 4
Round with very bright, stellar core, becoming weaker toward the edge.

Arp 273 (GLXGRP)

Image source: DSS II (blue) - 5×5'
Name: Arp273
Constellation: And
Coordinates: 02h21m30.00s / +39°22'00.00"

Group Members:
UGC1810 12m9 2.0x1.4' (20°)
UGC1813 14m2 1.1x0.3' (80°)
Very nice, but faint Arp group.

8" f/6, 171x, Bortle 4, NELM 6.0, SQM-L 20.9
SQM-L 20.4: Only the bright UGC1810 was visible: At 100x extremely faint brightening. At 171x oval or slightly elongated, quite faint and evenly bright.