What to Do If Your Night Vision Fogged Up or Stopped Working in the Field
Using night vision optics in the field is a serious challenge for both the device and the user. A single mistake or minor issue can be fatal, as there are no service centers or technicians nearby to correct any defects. Therefore, it’s important to properly prepare the equipment and consider all the nuances of its operation. This is the only way to minimize risks. However, if your NVD fogging stops working in the field, you can try to fix the issue. This article explains how to do this and outlines the specific steps to take in each case.
NVD fogging
Common causes of NVD fogging
Any optics can fog. If used improperly and important recommendations are not followed, even the best models cannot avoid this fate. This problem most often occurs due to sudden temperature changes. These occur when going outside into the cold or when quickly removing night vision optics from a heat-retaining case or cover. The problem is equally common with increased humidity. This occurs during rain, snow, or fog. Humidity also increases in the pre-dawn hours and when near water. A leak in the device’s seal is another common cause of this problem. Even a small crack in the housing is enough to let moisture in and cause lens fogging.
Step-by-Step troubleshooting
If you notice your NVD lenses are fogged up, don’t panic. A few simple steps should quickly resolve the issue. The first thing to do in the field is to calm down and ignore your inner urge to wipe the fogged lenses with your hand or sleeve. Such a thoughtless action will only worsen the situation and lead to further problems. Instead, turn off the fogged device. Then, place it in a warmer place (such as a protective case or an inside jacket pocket) and wait until the optics reach the same temperature as the surrounding environment (this may take 5 to 15 minutes). This will help evaporate any moisture on the lenses. Next, gently wipe the fogged parts of the device with a special cloth (sold separately or included with the device). After this, you can turn on the NVD and check the image quality.
Tips for preventing fogging
Today, protected from moisture, temperature extremes, and other factors are readily available. They are available from AGM and other leading manufacturers, making them affordable for everyone. However, even these devices require proper use. To ensure this, it is recommended to always keep the NVD in a case or holster and remove it only when in use. This will significantly reduce the risk of fogging. Another recommendation is to remember that human breathing also creates a temperature contrast and can lead to problems. Therefore, it is important to hold your breath when inspecting the objective lens and eyepiece. Finally, remember that using a device with a fogged-up interior is a significant risk.
NVD stoppage
Common causes of NVD stoppage
An NVD won’t work forever. In certain situations, it may shut down on its own, leaving you alone in the dark. This most often occurs due to a low battery. Once the NVD has exhausted all its power, it won’t turn on until you connect a backup power source (such as a spare battery or an external power source). Night vision optics also often stop working due to damage. Drops and contact between the casing and various hard objects can cause malfunctions of individual components or entire assemblies. In this case, field repairs are impossible.