Pull-down blinds in the photographer's darkroom aren't anywhere close to being able to shut out the light that would ruin film she was developing.
As a way to get a lead, Sgt. Benson poses nude for the men's magazine that's tied in to the people they're investigating. But due to the morals clauses of police departments, he would have undoubtedly faced disciplinary action, including termination, for posing nude in a magazine.
Jill's darkroom is clearly not a darkroom. Apart from the fact that it has a window in it, the walls are white (a real darkroom would have black walls to absorb the light), and the equipment is entirely new.
During quick close-up of newspaper when female photographer reads story headlined MALE MODEL SLAIN, the article has nothing to do with murder and is just a jumble of meaningless sentences.