I've always pictured the guys who write military operator manualsto be like Will Ferrell's character, Allen Gamble in "The Other Guys." If you don't understand the reference, go watch the movie. Basically, they turn the drill of powering on your NVG's into an administrative 20-step operation. Do they really expect us to go through all that crap in real life? Sadly, they probably do. But, let's get something straight: Operator's Manuals are meant to teach a five-year-old how to use a piece of equipment. They do not reflect realistic use of gear.
One of the questions/complaints we get a lot at TNVC is how certain mounts and adapters do not allow people to get the goggle all the way back to their eye(s) as it states they should in the NVG Operator Manual. This is usually because the user has purchased one of the Wilcox or Norotos mounts such as the INVG, L4 G24, and Wilcox PVS-14 Adapter Arm. The Operator Manual states that the goggle should be situated so it is fully seated against the face with the rubber eye cup forming a seal around the ocular socket and the mount adjusted so the user sees a perfect circular image. This is great in the lab, but in real life, it's complete bullshit.
Remember that NVG's and their accessories are designed for real-world use by Warfighters and Law Enforcement Professionals first. These jobs are rugged and require a ton of physical exertion. I have never been in the field and had my gear stay exactly where I put it. My helmet moves slightly on my head when running, climbing, etc. My body armor moves on my torso, etc. I don't want to tighten it all down so much that it stays exactly where I put it because then I would not be able to breathe. So, imperfect situations are something you just have deal with in the field. This is true of professionals and hunters alike. Basically, you may set your goggle up on your helmet so that you get a perfect circle image and it is all the way back at your eye while you are standing in the comfort of your home or the team room, but it won't stay that way in the field.
On top of that, you do not want to have the goggle all the way back against your eye as it suggests in the operator manual. Sure, it gives you an ideal image, but run around in the field for a bit and you won't see shit anyway. Why? Because all that physical exertion will cause your head and face to get so hot that your eyepiece will fog up and be covered in sweat. This is compounded when you are wearing armor. The body aspirates from the head and upper chest/back. This means you give off the most heat from these areas. The high end mounts and adapter arms mentioned above are favored by operators in SOF units for many reasons. But, one of the reasons is because they stand the goggle off the face so air flow can get between the skin and the lens. Sure, this sacrifices a bit of your perfect circle image, but you still have plenty to work with.
The real world ain't perfect. But, you should use your gear according to the laws of physics and not the laws of the operator's manual.[color=#00ff00]
-Chip
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