Best Thermal Scope in 2027: ATN ThOR 6 640 LRF 2-16x

By Marc Vayn, Founder, Chairman & CMO, ATN Corp

Thirty years ago I carried my first night vision unit into a garage in Silicon Valley and tried to explain to people why anyone would want to see in the dark. Last season I watched a sounder cross a cut cornfield at 280 yards and counted the animals before deciding which one to take. That is the gap this category closed, and it is why picking the best thermal scope now comes down to three numbers rather than a brochure: sensor resolution, thermal sensitivity, and the glass in front of them. I build these, so expect me to like them. What follows is still the honest version.

The ATN ThOR 6 LRF 640 2-16x is the best thermal scope for most hunters in 2027 at $2,595: a 640×512 sensor, ≤15mK thermal sensitivity, a 35 mm germanium lens, 3,100 m detection range and a built-in laser rangefinder good to 1,000 m. Spend more only for the 50 mm long-range build; spend less and you give up resolution before anything else.

Quick Answer: Which ATN Thermal Scope to Buy in 2027

• Best overall: ATN ThOR 6 LRF 640 2-16x — $2,595. The 640 sensor, the rangefinder and a wide 2x bottom end in one scope.
• Best long-range: ATN ThOR 6 LRF 640 3-24x — $2,995. A 50 mm lens, 3,650 m detection and ranging to 1,000 m.
• Best for hunting: ATN ThOR 6 640 2-16x — $2,295. The same optics as the overall pick, minus the rangefinder.
• Best in humid, low-contrast air: ATN ThOR 6 640 3-24x — $2,595. 50 mm of germanium collecting energy at ≤15mK.
• Best for the money: ATN ThOR 6 384 2.5-20x — $1,595. Full-size body, ≤15mK sensitivity, 384 sensor.
• Best compact premium: ATN ThOR 6 Mini 640 3-24x — $2,495. 640 resolution and 3,500 m detection at 580 g.
• Best lightweight: ATN ThOR 6 Mini 384 3.5-28x — $1,495. 540 g with a 35 mm lens and 2,710 m detection.
• Best budget pick: ATN ThOR 6 Mini 256 2-16x — $689. The entry into the 6th generation, at 500 g.

How We Picked These Eight Scopes

We picked these eight by ranking the current ATN thermal line against the published specifications that decide what you actually see in the dark, not by field impressions we cannot show you. Four numbers did the sorting, in this order.

• Sensor resolution — 256×192, 384×288 or 640×512. This sets how much detail survives when you zoom, and it is the one thing no processing recovers.
• NETD — ≤15mK on the full-size ThOR 6, ≤18mK on the Mini 640 and 384, ≤20mK on the Mini 256. Lower means the sensor separates smaller temperature differences, which is what matters in damp, washed-out air.
• Objective diameter — 15 mm to 50 mm of germanium at F/1.0. Bigger glass gathers more energy and stretches the detection figure.
• Weight and battery — 500 g to 855 g, and ~7 to ~9 hours. A scope you leave in the truck has no resolution at all.

What those numbers do not tell you: detection range is not identification range. A 3,100 m figure means the sensor can register a heat signature at that distance under the manufacturer's test conditions — not that you can tell a hog from a calf, and certainly not that you should shoot at it. Treat the detection column as a comparison between models, nothing more. Prices are the current promotional prices from ATN's own list and move with the season.

Why the 6th Generation Changed the Math

The 6th generation moved ATN thermal scopes from "good enough to find animals" to "detailed enough to decide," and the reason is a 12μm pixel pitch paired with ≤15mK sensitivity on the full-size models. Smaller pixels put more of them behind the same lens, so a 640×512 core resolves detail that a coarser sensor averages into a warm blob at the same magnification.

Sensitivity did the other half. At ≤15mK the sensor separates temperature differences small enough that a deer stays a deer against a sun-warmed field at nine in the evening, instead of fading into the background. SharpIR, ATN's image processing, cleans up what the sensor hands over; the explanation of how SharpIR works covers why two scopes with identical sensors look different.

Everything else in the line is shared, which simplifies the choice: 50 Hz refresh, six palettes (White Hot, Black Hot, Iron Red, Alarm, Green Hot and Sepia), 1920×1080 OLED on the full-size bodies, 64 GB of storage, Recoil Activated Video, Wi-Fi, IP67 sealing and a magnesium alloy housing. You are choosing a sensor and a lens, not a feature list.

ATN Thermal Scopes Compared: All Eight Picks

Best Overall Thermal Scope: ATN ThOR 6 LRF 640 2-16x

The ATN ThOR 6 LRF 640 2-16x is the best overall thermal scope in the 2027 line because it pairs the 640×512 sensor with a laser rangefinder and still opens at 2x, which is the combination most hunters use on most nights.

• Price: $2,595 · Sensor: 640×512, 12μm · NETD: ≤15mK
• Magnification: 2-16x · Lens: 35 mm germanium, F/1.0 · Detection: 3,100 m
• Weight: 855 g (1.89 lbs) · Battery: ~9 hrs, replaceable 18650 · Ranging: 1,000 m, ±1 m

The 2x bottom end is the part people underrate. A wide field at low magnification is how you find an animal; 16x is how you confirm it once you have. A scope that starts at 3x makes you hunt with a monocular in your other hand. The rangefinder earns its place the moment terrain stops being flat — it feeds the ballistic calculator a measured distance instead of your estimate, and at 300 yards an estimate that is off by 40 is a clean miss.

Buy this if you hunt varied country and want one scope to do everything. Skip it if every shot you take is inside 150 yards over a feeder — you are paying for range you will not use.

Best Long-Range Thermal Scope: ATN ThOR 6 LRF 640 3-24x

The ATN ThOR 6 LRF 640 3-24x is the long-range pick at $2,995, with a 50 mm germanium lens that pushes detection to 3,650 m and ranging accurate to ±1 m out to 1,000 m.

• Price: $2,995 · Sensor: 640×512, 12μm · NETD: ≤15mK
• Magnification: 3-24x · Lens: 50 mm germanium, F/1.0 · Detection: 3,650 m
• Weight: 855 g (1.89 lbs) · Battery: ~9 hrs · Storage: 64 GB

The extra 15 mm of objective is doing the work here, not the magnification number. A larger lens collects more infrared energy, which is why the detection figure climbs by 550 m over the 35 mm build while the sensor stays the same. The ballistic calculator matters more at this distance too: ranging, holdover and the shot all happen without taking your eye off the animal. If you want the physics rather than my summary, the piece on germanium optics explains why the lens is the expensive part.

Buy this if you shoot open country past 250 yards. Skip it if you hunt timber, where 3x at the bottom end is too tight to track a moving animal.

Best Thermal Scope for Hunting: ATN ThOR 6 640 2-16x

The ATN ThOR 6 640 2-16x is the best general hunting scope at $2,295 because it carries the same 640×512 sensor, ≤15mK sensitivity and 35 mm lens as the overall pick, without the rangefinder you may not need.

• Price: $2,295 · Sensor: 640×512, 12μm · NETD: ≤15mK
• Magnification: 2-16x · Lens: 35 mm germanium, F/1.0 · Detection: 3,100 m
• Weight: 830 g (1.83 lbs) · Battery: ~9 hrs · Palettes: six, including Iron Red and Alarm

Dropping the rangefinder saves $300 and 25 g. That is the whole difference. If you hunt country you know — the same fields, the same fence lines, distances you have already walked — you are carrying a laser to confirm what you could tell me in your sleep. Put the $300 into a mount and a second battery instead.

Buy this if you hunt familiar ground and already judge distance well. Skip it if you hunt new leases every season or shoot across canyons, where guessing is expensive.

Best Thermal Scope for Humid, Low-Contrast Air: ATN ThOR 6 640 3-24x

The ATN ThOR 6 640 3-24x is the pick for humid, washed-out conditions at $2,595, combining ≤15mK sensitivity with a 50 mm germanium objective — the two specifications that decide what you see when the air stops cooperating.

• Price: $2,595 · Sensor: 640×512, 12μm · NETD: ≤15mK
• Magnification: 3-24x · Lens: 50 mm germanium, F/1.0 · Detection: 3,650 m
• Weight: 830 g (1.83 lbs) · Battery: ~9 hrs · Sealing: IP67

Humid air carries heat away from everything and flattens the temperature spread the sensor is reading. When the whole scene sits inside a narrow band, sensitivity is what pulls an animal out of it — and ≤15mK is the lowest figure in this lineup. The 50 mm lens compounds it by collecting more signal to begin with. This is the same body as the long-range pick without the laser, so you get the glass and the sensitivity for $400 less.

Buy this if you hunt the Gulf Coast, river bottoms, or anywhere the dew point chases the air temperature. Skip it if you need ranging — the LRF version is the same scope with a laser.

Best Thermal Scope for the Money: ATN ThOR 6 384 2.5-20x

The ATN ThOR 6 384 2.5-20x is the best value in the line at $1,595 because it keeps the full-size ≤15mK sensitivity and the 9-hour battery while stepping the sensor down to 384×288.

• Price: $1,595 · Sensor: 384×288, 12μm · NETD: ≤15mK
• Magnification: 2.5-20x · Lens: 25 mm germanium, F/1.0 · Detection: 2,300 m
• Weight: 790 g (1.74 lbs) · Battery: ~9 hrs · Storage: 64 GB

Here is the honest trade: you are giving up pixels, not sensitivity. At ≤15mK this sensor separates temperature as well as the $2,995 scope does; it simply has fewer pixels to draw the result with, so detail thins out sooner as you zoom. Inside 200 yards you will struggle to tell the difference on a hog-sized animal. Past that, you will.

Buy this if most of your shooting happens inside 200 yards and you want the full-size body. Skip it if you already know you will be reaching past 300.

Best Compact Premium Thermal Scope: ATN ThOR 6 Mini 640 3-24x

The ATN ThOR 6 Mini 640 3-24x is the compact premium pick at $2,495 — a 640×512 sensor and 3,500 m detection in a 200 mm body that weighs 580 g.

• Price: $2,495 · Sensor: 640×512, 12μm · NETD: ≤18mK
• Magnification: 3-24x · Lens: 50 mm germanium, F/1.0 · Detection: 3,500 m
• Weight: 580 g (1.28 lbs) · Battery: ~7 hrs · Dimensions: 200×65×65 mm

Cutting 250 g and 230 mm off the full-size body costs you two things, and both are on the spec sheet: sensitivity goes from ≤15mK to ≤18mK, and runtime from about nine hours to about seven. On a lightweight rifle that trade is usually worth making — the scope stops dominating the balance of the gun, and you notice that on every stalk.

Buy this if you carry your rifle more than you rest it. Skip it if you sit in a blind all night, where the weight never mattered and the extra sensitivity does.

Best Lightweight Thermal Scope: ATN ThOR 6 Mini 384 3.5-28x

The ATN ThOR 6 Mini 384 3.5-28x is the lightest scope here that still carries a 384×288 sensor, at 540 g and $1,495.

• Price: $1,495 · Sensor: 384×288, 12μm · NETD: ≤18mK
• Magnification: 3.5-28x · Lens: 35 mm germanium, F/1.0 · Detection: 2,710 m
• Weight: 540 g (1.19 lbs) · Battery: ~7 hrs · Body: 190×65×65 mm, magnesium alloy

Three and a half power at the bottom end is the thing to think about before you buy this one. It is a tighter starting field than the 2x scopes, which makes picking up a moving animal harder — the trade you accept for a 35 mm lens on a 540 g body. The upside is real: on a light carbine this scope disappears, and 2,710 m of detection is more than most people will ever use.

Buy this if weight is your first constraint and you scan with a separate monocular. Skip it if the scope is your only way of finding animals in the dark.

Best Budget Thermal Scope: ATN ThOR 6 Mini 256 2-16x

The ATN ThOR 6 Mini 256 2-16x is the way into the 6th generation at $689, with a 256×192 sensor, a 15 mm lens and 1,200 m of detection range.

• Price: $689 · Sensor: 256×192, 12μm · NETD: ≤20mK
• Magnification: 2-16x · Lens: 15 mm germanium, F/1.0 · Detection: 1,200 m
• Weight: 500 g (1.10 lbs) · Battery: ~8 hrs · Display: 0.32" OLED, 800×600

At this price the question is not whether it matches the $2,995 scope — it does not, and the spec sheet says so plainly: a quarter of the pixels, ≤20mK instead of ≤15mK, and a smaller display. The question is whether it does the job close in, and inside 100 yards on a hog-sized animal it does. The processing, palettes and recording are the same 6th-generation package as the rest of the line.

Buy this if this is your first thermal and your shots are close. Skip it if you have hunted with a 640 — you will not go back, and you will buy twice.

How to Choose a Thermal Scope

Choose by the longest shot you will actually take, then by weight, then by whether you need ranging. In that order, because the first one is the only decision you cannot undo with accessories.

• Distance sets resolution. Inside 150 yards, 256×192 works. Out to 250, 384×288 is enough. Past 300, buy 640×512 — zooming a smaller sensor does not add detail that was never captured. The detection range explainer covers why the advertised figure and your working distance are different numbers.
• Conditions set NETD. Dry, cold air gives you contrast for free. Humid, mild nights do not, and that is where ≤15mK separates from ≤20mK.
• Lens size sets field of view. A 50 mm objective reaches further; a 15 mm objective lets you find things faster up close. The lens size and field of view guide has the trade in detail.
• Weight sets whether you carry it. 500 g versus 855 g is the difference between a scope you stalk with and one you set up with.
• Ranging is for unfamiliar ground. On known country you already have the distances. On new leases the LRF pays for itself in one season.

If you want the use-case version of this decision rather than the lineup version, the guides on the best thermal scope for hunting, hog hunting, coyote hunting and AR-15 builds each pick a winner for one job rather than eight.

Frequently Asked Questions

How much does a good thermal scope cost?

A capable thermal scope costs between $689 and $2,995 in the current ATN line. The entry is the ThOR 6 Mini 256 2-16x at $689; the 640-sensor models with a rangefinder run $2,595 to $2,995. Price tracks sensor resolution and lens diameter more than anything else.

Is a 384 or 640 thermal scope better?

A 640×512 sensor is better past roughly 250 yards, and a 384×288 sensor is enough inside that. Both ThOR 6 full-size cores carry the same ≤15mK sensitivity, so the difference is detail retained at magnification, not the ability to detect heat.

What does NETD mean on a thermal scope?

NETD measures the smallest temperature difference a sensor can register, in millikelvins, so lower is better. The ThOR 6 full-size models are rated ≤15mK, the Mini 640 and 384 ≤18mK and the Mini 256 ≤20mK. The gap shows up in humid air, not on crisp winter nights.

How far can a thermal scope actually see?

Detection ranges in this line run from 1,200 m to 3,650 m, but detection is not identification. Those figures mean the sensor registers a heat source at that distance under test conditions; telling species apart happens at a fraction of it, and an ethical shot at a fraction of that again.

Do I need a laser rangefinder on a thermal scope?

You need one if you hunt unfamiliar or broken ground past about 200 yards. The LRF models range to 1,000 m with ±1 m accuracy and feed the measurement straight to the ballistic calculator. On ground you know well, the $300 premium buys you convenience rather than capability.

How long does a thermal scope battery last?

Between about seven and nine hours across this lineup: ~9 hours on the full-size ThOR 6 bodies, ~8 on the Mini 256 and ~7 on the Mini 640 and 384. All run replaceable 18650 cells, so a spare in a pocket doubles your night.

Can you use a thermal scope during the day?

Yes — thermal imaging reads heat rather than light, so daylight does not blind it the way it does an image intensifier. Sun-warmed ground reduces contrast in the afternoon, which is why the palette you choose matters more by day than by night.

What I Would Put on My Own Rifle

The ThOR 6 LRF 640 2-16x, and I have said so to enough people at enough shows that nobody at ATN is surprised anymore. It is the one that stops me reaching for a second device: the 640 sensor to decide what I am looking at, the 2x bottom end to find it, and ranging so the ballistic solution rests on a measurement instead of a guess. If the budget is not there, the ThOR 6 384 2.5-20x at $1,595 gives up pixels but not sensitivity, and that is the right corner to cut. If you are moving up from an older ATN scope, the generation upgrade guide lays out what actually changes, and the Gen 6 field review covers half a year of use. The full lineup, with current pricing, is on the ATN thermal scopes page — go compare the two sensors side by side before you spend anything.