The Sidekick 640 runs a 640×480 core at 12 µm behind a 19 mm lens; the OTS LT 160 3-6x runs 160×120 at 17 µm behind 19 mm. The Sidekick 640 has 16.0× the pixels. On the Johnson yardstick they detect a person at 396 m and 279 m and recognize one at 99 m and 70 m; the boxes say 709 m and 430 m. The Sidekick 640 is lighter by 10.8 oz. Approximate prices are ~$3,299 and ~$799.
Estimated range, standing human, clear air
IdentifyRecognizeDetectBox claim
Armasight Sidekick 640640×480 · 12 µm · 19 mm
61 m identify99 m recognize396 m detectbox says 709 m (human-sized target)
ATN OTS LT 160 3-6x160×120 · 17 µm · 19 mm
43 m identify70 m recognize279 m detectbox says 430 m (human (ATN 'Human Detection Range', 475 yd))
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.