Hello,
In trying to establish the faintest magnitude stars on my Nereid 20 min sub frames, I located a
USNO website where you can enter the RA and DEC coordinates and obtain a chart of stars down to around 21 mag.
Having done this, I think that I may have candidate stars of fainter than 20 mag on my Nereid image. These are identified by the letters A & B in the attached files.
I write candidate as you can also see some speckles elsewhere in the cropped frame that are just noise and not “real” objects. Who knows?
Cheers
Dennis