PTZ Camera Coverage Radius on a Jobsite — Aim, Zoom, and Blind Spots

The industry standard (Australian AS 4806) defines three tiers:

Identification — you can identify a specific individual from footage. Requires 80+ pixels per foot of subject.

Recognition — you can recognize a known person or vehicle. Requires 20 pixels per foot.

Detection — you can see there's a person or vehicle. Requires 4 pixels per foot.

• Identification: 80+ ppf — 200–400 ft with 4K PTZ
• Recognition: 20 ppf — 400–800 ft with 4K PTZ
• Detection: 4 ppf — 600–1,200 ft with 4K PTZ
• Standard: Australian AS 4806 (industry norm)

Standard spec: 4x 4K PTZ cameras with 30x optical zoom and auto-tracking. Mount height: ~22 feet on the extended mast.

That mount height + zoom range gives identification-grade coverage across a 4-acre rectangular site with the four cameras aimed at 90-degree quadrants.

Directly under the trailer (0–25 feet radius) is a natural blind spot with a fixed-position PTZ. Guardtress deployments address this with a downward-fixed camera on the trailer chassis or a supplementary pole-mounted camera 40 feet from the trailer.

Corners of an irregular site beyond 400 feet from the trailer are the other common blind spot. Address with pole cameras or a second trailer.

• Under-trailer blind spot: 0–25 ft — fix with chassis cam
• Beyond-radius corners: fix with pole cam or 2nd trailer
• Perimeter fencing shadows: plan around at deployment
• Adjacent building shadows: rotate camera position seasonally

Four cameras at 90-degree quadrants is the default. On irregular sites, aim adjusts to concentrate on high-value zones and known intrusion paths.

Auto-tracking follows a subject once detected — the camera zooms and pans to keep the target in identification-grade frame through their movement across the site.