How Thermal Drones Can Help Search for Missing Pets

What does a thermal drone camera see?

A thermal camera does not produce a photograph in the normal sense. It measures infrared radiation reaching the sensor from the first surface in its line of sight and displays those differences as a picture of relative warmth.

That means it shows the top of whatever is between the camera and the ground: grass, bracken, a roof or a tree canopy.

Can thermal cameras see a dog or cat?

They can potentially detect an animal where there is a clear line of sight and enough thermal contrast between the animal and its background. Where either is missing, the animal may not appear at all.

What conditions help thermal imaging?

• Cooler surroundings, which may create stronger contrast against a warm animal.
• Open ground, which gives a clear view down to the surface.
• Early morning, evening or night, which can sometimes reduce heating from the sun.
• Settled weather and surface temperatures that are not close to body temperature.

No single time of day is universally best. Conditions on the day matter more than the clock.

What can reduce thermal performance?

• Warm ground and sun heated surfaces such as tarmac, stone and metal.
• Roofs, buildings, vehicles and machinery.
• Dense vegetation and tree canopy.
• Rain, fog and heavy damp air.
• Other animals producing similar signatures.
• Very small or very distant heat sources that fall below usable resolution.

Can thermal cameras see through walls?

No. Thermal cameras cannot see through walls, roofs, sheds, garages or vehicles. An animal inside or underneath a structure will not be visible from the air.

Can thermal cameras see through trees?

No. Branches, leaves and dense vegetation block the view in the same way a solid object does. Where an animal appears in woodland footage, it is being seen through a gap rather than through the foliage. This is explained in full in can a thermal drone see through trees.

Is every heat signature a missing pet?

No. A large share of what shows up during a search turns out to be something else entirely.

• Deer, foxes, badgers, rabbits and birds.
• Livestock in neighbouring fields.
• People walking, running or working outdoors.
• Vehicles, machinery and equipment left running.
• Surfaces still holding heat from the day.

Thermal compared with a normal camera

• Detects: thermal reads temperature difference, visual reads reflected light.
• Light: thermal works day or night, visual needs usable daylight.
• Identification: visual usually confirms what an animal is, thermal often cannot.
• Obstacles: neither sees through canopy, roofs, walls or vehicles.
• Best use: thermal to spot something worth checking, visual to confirm it.

When might thermal search be worth considering?

Thermal is most worth considering over open ground with a reasonably defined search area and cool, settled conditions, particularly when a large area needs covering quickly. See best conditions for a drone search.