Armasight Contractor 640 2.3-9.2x35 vs Armasight Contractor 640 3-12x50
The Contractor 640 2.3-9.2x35 runs a 640×480 core at 12 µm behind a 35 mm lens; the Contractor 640 3-12x50 runs 640×480 at 12 µm behind 50 mm. On the Johnson yardstick they detect a person at 729 m and 1,042 m and recognize one at 182 m and 260 m; the boxes say 1,305 m and 1,865 m. The Contractor 640 2.3-9.2x35 is lighter by 3.4 oz.
Estimated range, standing human, clear air
IdentifyRecognizeDetectBox claim
Armasight Contractor 640 2.3-9.2x35640×480 · 12 µm · 35 mm
112 m identify182 m recognize729 m detectbox says 1,305 m (human-sized target)
Armasight Contractor 640 3-12x50640×480 · 12 µm · 50 mm
160 m identify260 m recognize1,042 m detectbox says 1,865 m (human-sized target)
501002005001k2k5k m
Estimated from pixel pitch and lens focal length using the Johnson criteria (2, 8 and 13 pixels across a 0.5 m human critical dimension), clear air, 50 % probability. A model of the optics, not a measurement — real range depends on temperature contrast, humidity and the animal.