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Visible crew/equipment: Jesse and Mike are driving to the first pickup spot in the desert. The camera pans down over the windmill/pump with the car driving towards us and a classic BB desert scene in the distance. A cameraman is visible in the bottom right of the shot. (00:08:50)
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Visible crew/equipment: When Walter walks towards Jesse's house when he hasn't shown up for work a camera and boom microphone shadow is shown on his back. (00:40:10)
Box Cutter - S4-E1
Visible crew/equipment: When Skyler gets out her car after speaking to Saul, if you watch the chrome on the door you can see a boom mic moving. (00:18:25)
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Visible crew/equipment: When Walter is talking to the CCTV camera, a microphone is visible just below the 'C' in the word Cam. (00:29:54)
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Crawl Space - S4-E11
Visible crew/equipment: A camera in a black protective box is visible on the ground in the intersection during the crash sequence when Walt gets T-boned by an SUV. (00:24:48)
Chosen answer: It is part of the ritual for la Santa Muerte. It is a sign of humility and sacrifice.
djm