WHAT ARE INFRARED ILLUMINATORS (IR)?
Infrared illuminators produce a beam of light in the infrared spectrum, typically ranging from 850 nm to 940 nm, which is perfectly detectable by night vision devices. This allows for enhanced perception of subjects at greater distances. A discreet night vision device capable of seeing objects up to 100 meters away would greatly benefit from an additional IR illuminator. However, the resolution power of the night vision device, which determines its ability to perceive faint details, remains unchanged as it primarily depends on the diameter of the front lens (or digital sensor).
CAN I QUANTIFY THE REAL BENEFIT OF AN INFRARED ILLUMINATOR?
Unfortunately, this is a very broad question as several variables come into play, which may not be apparent through casual evening observations. Firstly, as mentioned earlier, night vision devices benefit from ambient light. Therefore, you may notice significant differences when testing your new IR illuminator in your well-lit garden under the presence of streetlights and perhaps a full moon, compared to using it in the mountains with minimal light pollution and during the new moon phase. Additionally, the subject being observed also matters; perceiving a deer at a distance of 150 meters is different from perceiving a hare. For these reasons, I have tested this illuminator for two months to provide a concrete assessment of its actual performance.
When it comes to the choice between 850 nm and 940 nm, another factor to consider is the provided wavelength. As it is known, different IR frequencies have varying levels of “power.”
The wavelengths that we are able to see fall between 380 nm and 700 nm, with anything above that being mostly invisible. However, wavelengths between 750 nm and 900 nm may exhibit a slight red glow when the IR torch is activated. If you are looking to purchase a completely invisible IR torch (perhaps for reasons of surveillance, security, or vigilance), it would be necessary to opt for a 940 nm IR torch. However, it should be noted that a 940 nm torch would be less powerful than an 850 nm IR torch (approximately 30-40% less powerful).