A crawlspace and an August attic are the two rooms your camera lives in
Nearly every filmable moment here happens in one of two hostile spaces, and each allows exactly one attempt.
Inside the Perimeter the ducts are under the house. A technician on his knees in a crawlspace has a headlamp, one free hand and no room to back up, so the clip that survives is short, close and shot before anything gets pulled apart.
Nobody reshoots a crawlspace. Whatever the phone caught on the way in is what you have, and red clay dust filming over the lens is the most common reason otherwise good footage is unusable.
Outside the Perimeter the air handler sits in an attic that has been heating since the sun came up. Assume one take, get it in the first minute up there, and be back down the ladder before the heat makes the decision for the crew.
Both rooms reward narration over pictures. There is not enough light or room for the image to carry the point on its own, so the technician has to say what he is looking at while he is still looking at it.
A clip light that clamps onto a joist costs less than an hour of labor and rescues more crawlspace footage than any phone upgrade ever will.