Visible crew/equipment: On the train, Jack hears Mac saying the track isn't finished, then Jack becomes aware of the broken emergency stop button. When Jack walks back over to Annie and tells her they have to jump, we can see the reflection of the standing camera operator on the right door's window, and the reflection of a crouching crew member (possibly boom operator) on the left door's window. Definitely crew given they're meant to be alone on the train. (01:45:55)
Visible crew/equipment: When Jack is running beside the bus and breaks the window to get the driver's attention, there's a reflection in the window of the bus of a cameraman (wearing a baseball cap) running alongside the camera. In the next scene where the bus pulls ahead, the reflection of the camera is larger and more noticeable. (00:34:35)
Visible crew/equipment: In the scene where Jack is taking off the handcuffs of the guy who shot Sam, you can see the top of a bald crew member's head with headphones on behind them.
Visible crew/equipment: A camera crane on a moving vehicle is visible in the bus' rear window reflection, just as it enters the empty 105 freeway via police escort, and its long shadow then follows, at the left side of the screen. (00:53:35)
Visible crew/equipment: When the bus is about to jump the bridge, you can see that the bridge is flat, apart from the broken part, but when the bus jumps over the bridge, there's wood and stuff piled up at the end, making it "kick". (01:03:35)
Visible crew/equipment: When the police officers on the LAX vehicle are attempting to rescue all the passengers by driving up beside the bus, there's a camera angle between the bus and LAX vehicle, as the people are jumping out of the bus onto the LAX vehicle. If you look closely, you can see camera crew reflections on the rear bus fender, and also a man sitting wearing a white shirt with sunglasses reflected in the window of the open LAX vehicle door.
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: In several shots of Tuneman in the Jaguar, you can see the camera and its lights reflected in his sunglasses.
Visible crew/equipment: After Lieutenant McMahon requests to be flown to the 105 freeway interchange, a camera operator can be seen standing beside an overpass column when the bus and police escort drive by. (00:52:50)
Visible crew/equipment: The side camera is visible in a couple of shots when the bus has to make the tight right turn, after the bus returns all the wheels to the ground, as it smashes into the cop car. (00:45:20)
Visible crew/equipment: As the end credits are starting, tracks used for a camera dolly can be seen along the left side next to the buildings. (01:50:55)
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: 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 the speeding bus takes the really sharp right curve, while it leans over on its left wheels, you can see the crew's tire rig lift under the bus that they used to keep it steady for this stunt. (00:50:10)
Visible crew/equipment: When Jack is talking to Howard Payne from the payphone, you can see the boom microphone's reflection on the phone receiver in several shots. (00:30:00)
Visible crew/equipment: Aside from the mysterious other trooper(s) reflected in the tarpaulin on the roof near the start, as Keanu Reeves runs past it, you can see the clear silhouette and red light of a cameraman filming the scene. (00:11:30)
Visible crew/equipment: The first bus explodes, and the traffic on the road mysteriously disappears. If you look down the road, there are construction barriers blocking off the entire road, which would not allow any cars to drive through.
Visible crew/equipment: In the scene where the bus is exiting the highway on that sharp curve there's a medium shot showing the bus from the driver side. Look closely at the driver, it's either a really ugly woman or that's a man in a wig driving the bus. (00:47:04)
Visible crew/equipment: When the bus is jumping the gap in the bridge, if you look closely in one shot, Sandra Bullock is not driving. Instead it's a large man that appears to be wearing women's attire.
Visible crew/equipment: Close to the beginning of the film we see Jack in a coffee shop and his friend walks in. When they both leave and Jack goes to his car, a cameraman is reflected in the car window after the palm tree. (00:26:40)
Answer: Ventilation shafts or roof panels.
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