When Val Waxman recovers his sight in the park, the angle where the sun light hits the buildings in the background is different than the angle where the light hits Val and Ellie.
As Al and Chau enter the revolving doors, the reflection of a crew member holding a white reflecting board can be seen in the windows.
In the scene where they pitch the film to Val (about 16:30 into the film) the boom is visible in the mirror.