Detection range is when you are able to see if something is there, or if you are able to determine that there is movement but not the details of the activity. Size does matter –  the larger the object is, the easier it is to see. Another contributing factor is the mount of ambient light you have (straight, moonlight, infrared light), the more light, the further you will be able to see.

The detection range of a good Gen 3 can be several times further than a Gen 1 device. Even the type of device will have a big impact on its detection range, where binoculars are inherently more capable at longer distances. Many clients immediately opt for larger focal lenses to see farther, but other factors must be taken into account, such as the sacrifice to overall field of view, portability, and hands-free operation. Even more important to consider is the quality of the larger focal lenses – the difference between a low cost F/1.8 and a high end F1/1.0 lens is night and day.

The data given in this article is approximated and based off an average of collected data of night vision devices with 1x magnification, in green phosphor with a diversity of the type of devices (monoculars, binoculars, goggles) with a number of varying factors such as FOM (resolution, signal-to-noise), F-number and overall quality of lenses, rain, snow, hail, wind, fog/mist/haze, temperature, surrounding landscape, presence/absence of external sources of light and light pollution. The data is an estimation only and used for the purpose of demonstrating a general realtionship ONLY.

The factors (and their definitions) provided below are not exhaustive, other factors may also affect low-light performance of a night vision device.