Tag Archives: Night Vision Refocus Lenses

Night Vision Quick Focus Caps

Using NVG’s for a multitude of Law Enforcement tasks presents some challenges from typical white light jobs. One of those challenges is that the NVG is focused at a given distance, typically at infinity. The problem with this is when you need to see or examine something at close range. This requires that the NVG be manipulated to change the focus point, which in turn creates a new issue being that you cannot discriminate something at distance because it is blurred. There are a few remedies for this, one of those remedies is to make a tight “OK” hand signal and place that over the objective lens. This blocks the number of photons entering the tube and changes the focus to being much closer. You can adjust the size of the “aperture” by simply making a tighter or looser “OK”. Benefit is it’s free and you always have it, down side is trying to determine the right size and also manipulate other things with the hand that is occupied making the “OK”. Several manufacturers make focus caps, they range in price from over $200 to $9. They all do the same thing, reduce the numbers of Photons entering the tube


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