Heat Spys Incorporate The Following Sighting Methods

Open Sight
Open sighting simplifies Heat Spy operation and keeps cost low. Spot size increases with distance and must always be smaller than the target size to achieve the instrument’s rated accuracy. Distance to spot size ratios are specified on all open sight Heat Spy models.


Enclosed Optical Sight
This sighting system allows more precise target definition with parallax correction at 4 ft. and 20 ft. Distance to spot size ratios apply and are specified for all Heat Spy’s incorporating enclosed optics.



Telescopic Sight
Some Heat Spy models offer telescopic sighting options for long distance (up to 300 ft.) or precise aiming applications such as bolts, wire, tubing, forgings, and castings. Telescopes provide sighting on the centerline of the infrared optics.


Laser Sight
A high coherence laser aiming beam adds a powerful dimension to precise temperature measurements. The laser places a visible red dot on the center of the target surface. The Heat Spy can be held in any position and at any level. It is especially useful in cramped areas and in
awkward conditions such as standing on ladders and platforms. The laser is very effective indoors under all lighting conditions and useful in low light conditions outdoors. Laser energy from low reflective targets such as painted surfaces or oxidized metals is considered safe
for viewing. All Wahl laser sighting systems meet Federal Safety Regulations. It is important to note that the laser beam is a sighting device only and that the displayed temperature when using a laser equipped Heat Spy is not the reading at the laser spot. The area being measured is always dependent upon the distance to spot size ratio of the Heat Spy.