When Iris and John go to visit Maurice Charlton, a reflection of the camera lighting is seen on the inside of the front door.
When Iris and John are traveling to the nursing home, they are seen crossing a bridge. This bridge is Magdalene Bridge and leads to East Oxford, yet The Vale House, where Iris Murdoch spent the final years of her life, was (and still is) in South Oxford.
When John gets his coat caught against the chair at the pub, a boom mic can be seen in the mirror behind him.