What you need to know about Night Vision tube cosmetics
Intensifier tube manufacturing is an intensive and elaborate operation involving the creation of insanely thin glass strands fused together for the microchannel plate, to indium seals between the layers of the tube. How does this pertain to me the user? As a result of the various intricacies and the many finite variables involved in the manufacturing process dark spots and pepper are an inevitable byproduct of these aspects. Whether it’s an emission point that has been ablated or perhaps incomprehensibly small particles within a layer or component of the tube, dark spots and pepper are to be expected. These are naturally occurring happenstances of how intensifiers are birthed. It’s normal to want an absolutely pristine, no dark spots, no pepper tube; but that isn’t the reality of image intensifier tubes or a realistic expectation.
Establishing realistic expectations is important no matter what device you’re shopping for. All tubes are allowed dark spots to a specific tolerance. Even the most high tier systems and tubes are allowed multiple dark spots. If they don’t exhibit spots then there will inevitably be pepper to some degree or extent. “Pepper” refers to spots not large enough to qualify as a dark spot. Typically .003” or less for L3H and .002” or less for ESA. The pepper spot in this video measures .001” and is not large enough to be considered a spot. This tube is a good example of an extremely clean tube representing the upper tier of cosmetics.
The most important aspect to understand on top of all of this is, typically, dark spots and pepper aren’t noticed in actual use. Looking at a blank wall you can find pepper in any tube, even if it has no dark spots. Using your device in any situation other than looking at a blank wall not only will pepper not be noticed, but most dark spots will blend into the environment as well. Think of how you drive your car every day and don’t notice the spots on your windshield unless you seek to notice them. We hope this puts some background in understanding certain aspects of tube cosmetics and expectations with them. As always you’re welcome to reach out with any questions.
Demonstration video below