Night vision & thermal - the same? Not at all!

"What’s the difference between thermography and night vision?” This is a frequent question we get. Both technologies are phenomenal resources, providing information that the human eye can literally not see. Yet, they operate on distinctly different technologies. This overview summarizes how each works. 

Thermography

Thermal imaging or infrared (aka IR) is the process of acquiring and analyzing thermal data from non-contact, thermal imaging devices. Everything that is above Absolute Zero, which is 0⁰ Kelvin (converts to a very cold -459.67⁰ F) has molecular activity and can be captured by thermal imaging. Infrared is the actual, visual representation of thermal differences of objects. Thermal imaging:

  • Show heat variations 
  • Does not require a light source needed– the data is unaffected by light
  • Has no contact with objects

The major difference is light. For IR, light is irrelevant - it's all about the heat. But, do keep in mind that the heat radiating from or onto an object does have an effect (i.e., shadowing). We'll save that for a future post. 

Night Vision

We've all seen it - in the movies, on the news, by the military, etc. And, we're fascinated by it. It seems to have the ability to uncover hidden figures. But it cannot see everything and can be cloaked by objects - notice the picture. Here are the basics for night vision:

  • Requires some light source – albeit, minimal, but some contrast needed
  • Does not show heat variations
  • Has no contact with objects (same as thermography)

This video does a great job of depicting the differences - https://youtu.be/rAvnMYqj2c0

Remember, thermal imaging is all about “seeing” heat, and we help clients identifying thermal anomalies that night vision and the human eye would otherwise not see.