Zeiss · DTI 6/40

Estimated range, standing human, clear air

IdentifyRecognizeDetectBox claim

Zeiss DTI 6/40640×480 · 12 µm · 40 mm

128 m identify208 m recognize833 m detectbox says 2,000 m (unspecified)

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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.

Zeiss

Zeiss DTI 6/40

Handheld monocular640-class

The Zeiss DTI 6/40 is a 640×480, 12 µm thermal handheld monocular behind a 40 mm lens. On the Johnson yardstick that is an estimated 833 m detection and 208 m recognition range for a standing person; Zeiss quotes 2,000 m detection. It is the heaviest of the 18 handhelds here, at 26.6 oz.

Approx. price: ~$4,800
Sensor: 640×480 · 12 µm
Lens: 40 mm · 3×
Est. detection: 833 m · 911 yd

Best for

Scanning from a stand, a truck or a field edge

No verified retailer link for this unit yet. Only links confirmed to open the right product are published — here’s why.

Box claim vs. what the optics support

Manufacturer says

2,000 m

detection, unspecified

Johnson estimate

833 m

detect · 208 m recognize · 128 m identify

Claim ÷ estimate

2.4×

how much further the box reaches than a 2-pixel, 0.5 m criterion

One pixel of this unit sees 0.300 mrad (12 µm ÷ 40 mm). Two pixels across a 0.5 m human is 0.5 ÷ (2 × 0.300) × 1000 = 833 m. The box figure is usually computed against a person’s 1.8 m height instead, which is why it comes out higher. Full explanation.

Specifications

Manufacturer-published figures, cross-checked against opticsforce.com (full spec table; $4,799.99 sale, sold out on the day read; zeiss.com product pages 404 during site migration).

Sensor: 640×480
Pixel pitch: 12 µm
NETD: ≤35 mK
Refresh rate: 50 Hz
Lens: 40 mm
Base magnification: 3×
Digital zoom: up to 10×
Field of view: 11° horizontal
Display: 1024x768 AMOLED
Claimed detection: 2,000 m
Claim basis: unspecified
Run time: 6.5 h
Weight: 26.6 oz
Length: 9″
Laser rangefinder: No
Ballistic calculator: No
Records video: Yes
Wi-Fi: Yes
Approx. price: ~$4,800

Derived here

IFOV: 0.300 mrad
Est. detection: 833 m
Est. recognition: 208 m
Est. identification: 128 m
Claim ÷ estimate: 2.4×
Derived field of view: 11°
Pixels per degree: 58.4

Features

640 sensor
12 µm
40 mm lens
50 Hz
Records video
Wi-Fi
AMOLED display

What the spec sheet says

Read from the published specifications and this catalog’s own numbers — not from owner reports, which we have not collected for this unit.

For it

640×480 core — 2.8× the pixels of a 384-class unit
12 µm pitch — the 40 mm lens sees what a 17 µm core would need 57 mm to match
Records video and streams to a phone over Wi-Fi
Detection claim is only 2.4× our estimate — one of the more conservative box figures here

Against it