Declination pointing problem

• Date and time: Sep. 1, 2016 [0:37 UT − 0:47 UT]
• Exposures: 180 s
• RA, DEC: 23h 04m 11s, +2d 13m 34s
• Telescope position: Reverse (West of the pier), South is Up
• Differential tracking: 0.31 "/min, P.A. 251 deg