I attempt to go deep in an Abell galaxy cluster once or twice each new Moon cycle. On 4/7/21 I targeted Haumea, picking up various galaxies nearby. Close to this field was AGC 1913, so I made a finder chart for the session to see how many members/galaxies in the field I could pick up with the 20" in dark sky.
First up was dwarf planet Haumea, using my printed chart from SDSS images, with Haumea's position marked from MPC ephemerides. Despite being in the range of 17.3 magnitude, I saw it immediately in averted vision at 278x, precisely where I had plotted it relative to the key sets of two 13 mag, a pair of 15 & 16 and a 17 mag mag field star. Well west of the 17 mag star at 357x I could just make out PGC 1500912 (17.5 g mag), xxF, xxs, just hints mostly but enough to know it was there. To the NE of the group of stars near Haumea was CGCG 104-16 at a more recognizable 15.6 g mag, xs, vvF, elongated 2:1 NNW/SSE, with good surface brightness, 16 mag star just W of center. The only other galaxy I could see nearby was PGC 84153 (KUG1421+164) which was nearer the 6.9 mag star for my star hop. This one wasn't too hard at 16.1 mag, xs, xF, good SB, some brightening to middle but core not seen.
Then it was show time for AGC 1913 at about 750+ MLY distance. I located the cluster by first observing galaxies IC 4429 and IC 4426 that point to the center of it at 278x. From there I began working through the brighter members to the NW, CGCG 104-21/22/23/26 (all about 15.2 to 15.6 g mag), then PGC 51544 and 84181 somewhat south. Then I skipped to CGCG 104-27 near center, then to the far NW for PGC 84169 up against the glare of a 10th mag star.
After that I went after dimmer members in the center of the field PGC's 84176, 84179, 84178, 84174 in the 16.1 to 16.7 g mag range, as well as PGC's 51558, 51576, and 51580 in the 15.4 to 16.2 g mag range. I then chased down a string to the SE of PGC's 51609, 84187, 84188, and 84189. These ran from 15.7 g to 16.9 g mag. The final galaxy I observed was CGCG 104-19, which is perhaps a bit more distant and is somewhat detached from the group.
At this point I was having more difficulty seeing galaxies, and looked up to find thin cirrus was beginning to wash out the sky. It wasn't my eyes, the already marginal transparency had failed me. There were a few more outliers that would have been in reach, plus IC 4417, but the weather had other ideas.
Edited by Redbetter, 13 April 2021 - 04:47 AM.