Anabon field guides · Surveillance Knowledge
Storage, bandwidth, PoE budget and lens calculations for quoting commercial camera systems correctly the first time.
How to take a site from 8 to 16 or 32 cameras while keeping every cable: when an external PoE switch is enough, when the recorder changes, what carries over, and the upgrade-day checklist.
Rules of thumb for the camera count by site type, the counting method behind them, which CASE NVR each count points to, and why the site survey, not the table, decides the final number.
Why remote viewing stalls on mobile data and how to plan it: main vs sub stream, per-camera sub-stream resolution and bitrate, the outgoing bandwidth printed for each CASE NVR, and the arithmetic for several viewers at once.
One recorder or two for a two-building site? The link options, what crosses the link in each design, what happens when it drops, and a CASE comparison of two CS-N220 P16H-AI against one CS-N440 M-AI.
How to plan Cat6 runs for IP cameras: the 328 ft (100 m) channel, how patch panels and cords use the budget, where the PoE switch goes in a large building, fiber between buildings and a sample cable plan.
A one-page security camera lens angle chart: horizontal field of view, scene width at 16, 33 and 66 ft (5, 10 and 20 m) and pixels per foot against the DORI levels, with CASE examples and the formula behind it.
Megapixels only become detail through the lens: 8MP at 2.8 mm identifies a person to about 26 ft (8 m), not 98 ft. Computed distances for 4MP, 5MP and 8MP, low-light and storage trade-offs, and CASE examples per job.
An NVR supports as many cameras as the lowest of three limits allows: printed channels, PoE ports (cameras beyond them arrive through a switch) and incoming bandwidth. The CASE NVR table as printed, with the 20-channel, 16-port example.
Scene width = distance × sensor width ÷ focal length; pixels per foot = horizontal pixels ÷ scene width. Run it against the DORI levels before choosing 2.8 mm, 4 mm or a motorized varifocal lens, with CASE lens examples.
H.265 needs roughly half the bits of H.264 for the same picture; S+265 reduces the bitrate further on static scenes. What that means for drives, NVR bandwidth, decoding load and third-party platforms, with the one sourced S+265 figure.
