Visible crew/equipment: When McMahon is giving Jack directions to the vacant 105 freeway, a well-dressed crew member wearing sunglasses and a big grin is visible sitting in the aisle of the bus. (00:49:50)
Visible crew/equipment: In several shots of Tuneman in the Jaguar, you can see camera lights reflected in his sunglasses.
Visible crew/equipment: When Jack is talking to Howard from the pay-phone, you can see the boom microphone's reflection in the phone in several shots.
Visible crew/equipment: The camera operator and camera are visible reflected in Tuneman's sunglasses. It's especially evident right before he crashes into the water barrels.
Visible crew/equipment: After Keanu steals Tuneman's car there is an overhead shot from a helicopter as he's trying to catch up. The shadow cast by the helicopter is visible at the beginning of this shot.
Visible crew/equipment: When the guard walks past the pillars at the start, on the first pillar you can see a shadow made by the film crew. (00:03:00)
Visible crew/equipment: After the bus exits the freeway, as it drives on the city's streets the forward looking street-level action camera is visible, mounted behind the tire. (00:49:05)
Visible crew/equipment: In the scene after the bus gets off the on ramp and hits a bunch of cars, there is a rear facing shot. The shadow of the camera that is attached to the bus is visible during most of the shot.
Visible crew/equipment: When Payne is going crazy on the subway train, and starts shooting his gun at Jack on the roof, in one shot before Jack drops his gun, you can see a camera come in the shot. (01:42:50)
Visible crew/equipment: As Jack inspects the bus's speedometer for signs of tampering, a camera can be seen in a reflection on the window to Annie's left. (00:44:35)
Visible crew/equipment: As Harry walks out of the office after telling his colleagues to search for their mystery bomber via pension fund files, a boom mic pole is reflected in the left window when he says, "I've seen this a**hole." (00:55:25)
Visible crew/equipment: When Jack is trying to pry open the subway train's doors, a boom mic can be seen mounted on the car's interior, suspended from the ceiling. (01:40:30)
Visible crew/equipment: During the passenger transfers at LAX, a cameraman is visible through the bus doorway two shots before Annie glances over her right shoulder twice. (01:27:35)
Visible crew/equipment: When Jack is running alongside the subway train trying to find a way in, a camera and its operator can be seen on the window's interior reflection. (01:40:20)
Visible crew/equipment: When Jack's Bronco weaves across two lanes of traffic on the highway seconds before throwing it in park to catch up with the bus on foot, a camera can be seen, mounted in the Bronco's back seat. (00:34:15)
Visible crew/equipment: A film truck is reflected in the bus's bumper when Jack exits and steps onto the Suburban. (01:11:15)
Visible crew/equipment: When Jack flashes his badge at Tuneman, a camera's shadow is visible on the pavement. (00:35:00)
Visible crew/equipment: Right after the bus passes 50 mph and arms the bomb, filming equipment can be seen in the Jaguar's vent window reflection. (00:36:45)
Visible crew/equipment: When the credits are rolling, a crew member in a gray shirt on the lower left portion of the screen can be seen waving extras into the street. (01:51:05)
Visible crew/equipment: When the bus is traveling on the shoulder, a camera truck is visible to the extreme left immediately before Annie asks whether or not she should stay on the highway. (00:46:35)
Answer: Ventilation shafts or roof panels.
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