(at around 8 mins) The photograph on the bulletin board at the guard desk that Martin notices when he shows up for his first shift and asks the old watchman about, is a famous photo of Lewis Thornton Powell (also known as Lewis Paine or Lewis Payne), a conspirator with John Wilkes Booth, the assassin of Abraham Lincoln.
The movie is a remake of the Danish movie Nightwatch (1994). The director of the Danish original, Ole Bornedal, also directed the remake.
Miramax wanted to reshoot several of Ewan McGregor's scenes after his character received low scores from audiences in test screenings. McGregor refused to do so.
(at around 8 mins) The black and white picture of the guy on death row in the cabin is the same one used in the original version of this movie (Nightwatch (1994)).
The end scene where Martin and co. leave the morgue was a reshoot that occurred several months after principal photography had wrapped. If you look carefully, you can see that Josh Brolin's hair is slightly longer than it had been in the prior scene, and that it matches the hairstyle he had in Mimic (1997), which was being filmed by Miramax around the same time as the reshoot.