The question “How far can I see with this device?”,  is at the top of our FAQ list. The general term “seeing” means “seeing something” (detection), “seeing an object” (recognition) or “seeing an object in detail” (identification). Distances are determined by a number of factors that we separate in two groups: inner andouter.

 

Inner Factors (device-dependent):

  • Resolution of IIT
  • Signal-to-Noise ratio of IIT
  • Photosensitivity of IIT
  • Front lens focal length and f-number

Outer Factors (environment-dependent):

  • Object Size
  • Weather Conditions
  • Landscape
  • Lighting Conditions

 

Unlike thermal imaging where lighting conditions have literally no effect on thermal device’s performance having even a miniscule amount of ambient light is vital for successful operation of a night vision device. For example, if you have a good quality Gen.3 device with 1X magnification lens, then at full moon you will be able to see a vehicle at about 1200m. If it was an overcast night operating distance would reduce by whopping 50%, down to 600m.

To further emphasize the importance of weather and lighting conditions we provide a list of most influencing factors: rain, snow, hail, wind, fog/mist/haze, air pressure, temperature, surrounding landscape, presence/absence of external sources of lights and light pollution.

 

Conclusion.

 The key to achieving best possible results in detection, recognition and identification is in choosing the device with highest values of Resolution, SNR and sensitivity. But keep in mind that enviromental factors may significantly affect detection, recognition and identification distances.