Camera counts are the wrong place to start. Coverage planning starts with what must be answered later: who came in, what happened at the dock, which car hit the barrier. Work backwards from the questions and the layout draws itself.
1. List decisions, not locations
“Identify faces at reception” needs a different camera and mounting height than “see whether the yard gate is open.” Write each requirement as the question footage must answer, then match resolution and lens to the distance involved.
2. Cover approaches, not just doors
A face-on shot of the entrance is gold; a top-of-head shot from directly above the door is nearly useless. Mount cameras a few meters back from the choke point, looking along the natural approach path.
3. Mind the light, then the dark
Backlit lobbies and dusk car parks defeat more cameras than distance does. Note where the sun rises and sets on the plan, and let IR range decide the night layout — not the daytime walk-through.
4. Leave headroom in the recorder
Sites grow. Choose the recorder with a third of its channels free and the switch with PoE budget to spare, and the next two cameras cost a bracket and a cable instead of a new core.
