Range guide
How Far Can the Pulsar Thermion 3 Identify a Fox, Pig or Deer?
By our estimate from Pulsar's lens and sensor specs, the Pulsar Thermion 3 LRF recognises a fox at roughly 220–290 m, a pig at roughly 440–580 m and a fallow deer at roughly 560–750 m. To identify a fox with confidence, such as telling it from a cat, you'll want it inside about 145 m. The XR60 and XT60 give the same figures, because they share the same 60 mm lens and pixel size.
These are clear-night numbers. Humidity, rain and fog pull them in.
How we worked it out
Pulsar doesn't publish recognition distances, so we calculated them. Both Thermion 3 models use 12 µm sensor pixels behind a 60 mm lens, so each pixel covers about 2.0 cm at 100 m, 4.0 cm at 200 m, and so on. From there we apply the Johnson criteria, a long-standing rule of thumb for thermal and night optics. About 2 pixels across an animal's height lets you detect something warm. Around 6 to 8 pixels lets you recognise what kind of animal it is, and about 12 lets you identify it with confidence.
The diagram below shows a fox about 35 cm tall and 65 cm long at three distances.
Say you're scanning a dam bank at dusk, and a warm shape is working the far edge about 200 m away. On the Thermion 3 it's around 9 pixels tall: enough to see the shape of a fox, its tail and the way it moves, but not quite enough to be certain at a glance. Let it come in to 150 m and the outline firms up to identification level. At 400 m the same fox is a warm blob a few pixels high; you know something's there, and that's about all.
Distances for common Australian game
The chart below runs the same sums for the animals most Thermion 3 owners will hunt. Heights are approximate, measured at the shoulder. Identification needs about 12 pixels, so it sits at roughly two-thirds of the recognition distance.
For foxes and rabbits, the Thermion 3's reach comfortably covers normal night shooting distances. For pigs and deer it goes further than most hunters would shoot at night, which is where the 1,200 m rangefinder and ballistic calculator earn their place. A warm target shows up as a detectable dot at roughly three to four times the recognition distance.
Body position changes all of this. A fox side-on shows its full length; one facing you head-on shows little more than its height. Treat every figure here as a best case and check the animal before you decide anything.
What the 2,800 m detection range means
Pulsar rates both models to detect a target at 2,800 m. That's the distance at which a large warm animal first appears as a couple of pixels, with nothing to say what it is. The chart below sets it against the practical figures.
Detection range is useful for comparing scopes measured the same way, not for planning shots. You'll find more than one detection figure quoted for this scope; we use the 2,800 m in Pulsar's US specifications.
Weather, zoom and the XT60
Water in the air absorbs and scatters the infrared that animals give off. On a humid night, after rain or in fog, contrast drops and every distance above shrinks, more so the thicker the moisture. The XR60's slightly lower system NETD, under 18 mK against under 20 mK, helps a little on muggy nights; we explain why in how NETD affects the thermal picture.
Zooming in doesn't push these distances out. All of the Thermion 3's magnification is digital, so it makes the animal bigger on the screen without adding pixels to it. The same goes for the XT60's bigger sensor: it shows a wider scene, as we cover in Thermion 3 XR60 or XT60: is the 1280 sensor worth it, but each animal gets the same pixels as on the XR60.
If recognition distance is your top priority, a longer lens is what moves it. The 75 mm HIKMICRO Stellar 4.0 SX75L reaches roughly 25% further than the Thermion 3 by the same method, as we show in how far the Stellar 4.0 can identify a fox, pig or deer. For most fox and pig work on Australian farmland, though, the Thermion 3 already reaches past where you'd sensibly shoot. The full model rundown is in our Pulsar Thermion 3 LRF review.
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Thermion 3 LRF XR60 Thermion 3 LRF XT60Pulsar Thermion 3 range FAQ
Can the Pulsar Thermion 3 recognise a fox at 200 m?
Yes. By our estimate from the lens and sensor specs, a fox about 35 cm tall covers around 9 pixels in height at 200 m on the Pulsar Thermion 3 LRF, inside its estimated recognition reach of roughly 220–290 m. You'll see a fox shape and movement. For confident identification, such as ruling out a cat, let it come inside about 145 m.
How far can the Pulsar Thermion 3 recognise a pig?
By our estimate, the Pulsar Thermion 3 LRF recognises a pig about 70 cm tall at roughly 440–580 m and identifies it with confidence at about 290 m, on both the XR60 and XT60. That's further than most hunters shoot at night. Use the 1,200 m rangefinder to confirm distance, and expect shorter figures on humid or foggy nights.
How far can the Pulsar Thermion 3 see a deer?
By our estimate, the Pulsar Thermion 3 LRF recognises a fallow deer about 90 cm tall at the shoulder at roughly 560–750 m, and identifies it at about 375 m. It will show a deer as a detectable warm shape well beyond that. Identifying a buck from a doe needs more detail, so expect to be considerably closer for that call.
How far can the Pulsar Thermion 3 see a rabbit?
By our estimate, the Pulsar Thermion 3 LRF recognises a rabbit about 20 cm tall at roughly 125–165 m and identifies it at about 85 m. A rabbit sitting low in grass shows less of itself, so real distances are often shorter. For rabbit shooting inside about 100 m, both the XR60 and XT60 give plenty of detail.
How far can the Pulsar Thermion 3 recognise a wild dog?
By our estimate, the Pulsar Thermion 3 LRF recognises a wild dog about 55 cm tall at roughly 345–460 m and identifies it at about 230 m. Telling a wild dog from a working dog or a fox at the long end of that range is harder, so close the distance or wait for a side-on view before making the call.
What does the Pulsar Thermion 3's 2,800 m detection range mean?
It's the distance at which a large warm target, such as a deer, first appears on the Pulsar Thermion 3 LRF as a couple of pixels, with no detail to say what it is. Pulsar's US specifications rate both models at 2,800 m. By our estimate, you'd recognise a fox only inside about 290 m, so use detection range to compare scopes, not to plan shots.
Does fog or humidity shorten the Pulsar Thermion 3's range?
Yes. Water droplets in the air absorb and scatter the infrared that animals give off, so humidity, rain and fog all reduce contrast and shorten every distance the Pulsar Thermion 3 LRF can manage. The XR60's system NETD of under 18 mK helps slightly on muggy nights. In thick fog, expect much shorter recognition distances than our clear-night estimates.
Does zooming in on the Pulsar Thermion 3 add detail?
No. All of the Pulsar Thermion 3 LRF's magnification is digital, so zooming makes an animal bigger on the display without adding sensor pixels to it. Zoom helps you look closer at a shape you've already found, but recognition distance is set by the 60 mm lens and 12 µm pixels. At high zoom the picture shows visible pixelation.
All recognition and identification distances in this guide are our estimates, calculated from Pulsar's published Thermion 3 LRF lens and sensor specifications using the Johnson criteria.