Continuity: As Ben and Jane drive down the road, it is raining. After they hit the ghost, the scene fades to black. When the scene fades back in, it's heavily snowing, and a previously nonexistent thick sheet of snow is covering the ground. As they get out of the car, they start talking. During their conversation, there is a quick cut, and with this, it instantly stops snowing.
Continuity: When the ghost touches Ben's neck while he is in the darkroom, the arm shown is clad in dark wool identical to his wife's sweater. The phone rings and when he answers it, it's his wife, leading Ben to realize something is wrong. When he goes back into the darkroom, he is confronted by the ghost, which is not wearing dark clothing, but rather the pale dress she is seen in throughout the film.
Continuity: When Ben gets ready to take his and Jane's picture at the cabin, Jane is standing on Ben's right. When Ben gets the pictures back, Jane is now standing on Ben's left.
Revealing mistakes: When Ben and his wife take a picture of themselves in the beginning, the camera is obviously not on.
Factual errors: While in the honeymoon cabin, the camera Ben is using is clearly a medium format camera. Later however, when they are looking at the pictures Seiko dropped off, the negatives attached to the envelope are 35mm negatives.