July 2026 - Written by the HeatSight Optics Team
HeatSight TPM C19-640 54mm LRF Review - The C19-640 54mm LRF is the long-range problem-solver of the C19 line: a 640 core behind 54 mm of germanium, 2.5x base magnification, and a 1,500-meter laser rangefinder. Long shots are exactly where ranging matters most, which makes this the most logical LRF pairing in the family.
A compact tube-style thermal at 780 g with a 54 mm manual-focus germanium objective and 2.5x base magnification, expanding to 2.5-8x with electronic zoom. Dimensions are 196.5 × 96 × 66 mm. It mounts like a day optic and disappears on the rifle compared to the 3-pound LRF flagships from the big brands.
Every C19 shares the same 640×512 VOx core: 12 μm pixel pitch, ≤40 mK NETD, ≤50 Hz refresh, 8-14 μm band, manual focus, and a sharp 1440×1080 OLED display - a meaningful resolution step over the 1024×768 eyepieces common at this tier. Six palettes (White Hot, Black Hot, Fire Hot, Rainbow, Iron Red, Cold Color), picture-in-picture, hotspot tracking, and five menu languages are standard. Recording is onboard: 16 GB storage (13.8 GB usable), JPG/MP4, USB charge and export.
Power is a pair of removable 18350 cells (1,400 mAh each) rated for 5+ hours at ≤1.8 W. 18350s keep the scope compact, but they're less common at the corner store than 18650s - buy two spare pairs with the scope and rotate them. The housing is IP66 and rated to 1000G of recoil, operating -20°C to +60°C.
The built-in LRF ranges 10 m to 1,500 m with ±1 m accuracy inside 400 m (±0.4% beyond). On a thermal, where depth perception is nil, a one-button range reading is the difference between a confident hold and a guess - especially on coyote-sized targets past 150 yards.
Checked against known distances, the rangefinder reads true within a couple meters and does it instantly, which is all I ask of it. At the ranges this scope encourages, past 200, the number is not a convenience, it is the shot. Range, hold, press. The workflow never touches a phone.
This is the open-country configuration: the 54mm objective buys native magnification and detection reach, and the LRF makes the distance honest. I work it from set positions over big fields where the narrower view does not cost me anything and the extra legs on the sensor pay every night. Heavier than the 35mm, worth it where the shots are long.
Full 640×512 sensor at this price: Most competitors at this money are selling 384 cores.
1440×1080 OLED display: Sharper eyepiece image than the 1024×768 norm in this class.
Reach plus ranging: The configuration where an LRF earns its keep every single night - long-country shots demand real distance data.
Compact and light: 780 g on the rifle, standard mounting.
If your shots regularly stretch past 200 yards, this is the C19 to own. The rangefinder turns the 54mm's detection advantage into hits instead of educated guesses. 2-Year Limited Warranty, as with every HeatSight scope.
Specifications: 640×512 VOx, 12μm, NETD ≤40mK | 54mm, 8.1° × 6.5° | 2.5x base, 1-8x e-zoom | LRF 10-1,500m, ±1m <400m | OLED 1440×1080, 0.39" | ≤50Hz | 6 palettes, PiP, hot tracking | 16GB, JPG/MP4, USB | 2×18350 1,400mAh, ≥5h | -20°C~+60°C | 1000G | IP66 | 196.5 × 96 × 66 mm | 780g
The HeatSight Optics TPM C19-640 54mm LRF is available at heatsightoptics.com for $1,899. Check the product page for current stock - this model sells through quickly; contact us to get on the list for the next batch. Questions about which HeatSight scope fits your hunting or property-security setup? Call us at (313) 338-8168 - you'll talk to the people who actually build and flash these units, not a call center.
This review was written by the HeatSight Optics team based on our own design, bench, and field testing of production units. We build these scopes, so consider the source - and consider that we also publish the cons, because we'd rather you buy the right scope than return the wrong one.