After the film premiered at the Sundance Film Festival, Robin Williams overheard viewers say that they forgot it was Williams in the lead role 15 minutes into the film. An observation that made Williams proud.
In preparation for his role, Robin Williams trained for two and a half days at a photo developing training facility in Southern California on an Agfa MSC 101-D photo developing machine.
During the scene in which Sy discusses an elderly customer who has him develop never-ending photos of nothing but her cats, the photos shown of each cat were photos that the cast and crew had brought in of their own pets according to the American Humane Society. It was seen as a way to get more natural-looking cat photos instead of staging shots with trained animals.
Several of the family photos Sy goes through at the flea market feature Mark Romanek as a boy, his parents and his aunt.
Near the beginning of the movie, as the Yorkin family is going over their set of developed photos while in their house, they are eating Chinese food and inside of an opened fortune cookie it reads, "Someone wants you to be happy". Director Mark Romanek searched through 30 fortune cookies before he found one that related to the film and used it in the scene.