There's an inexpensive thing you can do that might help. As said before, Gen I stuff needs some kind of illumination to be able to see.
If you're in a static position looking out with Gen I NV, you can set up your own illum. "Illumination" means pretty much dim red lights. Something as simple as a light with a bunch of red backup-light repair tape from AutoZone, over the light, will light the area up like daytime to Gen I NV.
The "illum" can be really really dim to the naked eye and still be very effective to the early NV.
As a science experiment thing, get some (less expensive) Gen I NV and walk around your neighborhood at night with it- you'll be able to see your neighbor's security cameras because most of them use IR or dim red light to light up the area in front of the camera. When you look at a lot of home security cameras up close at night, they have some dim red LEDs lighting the area up so that the camera can see.
You can put the dim red lighting somewhere else than where you are, and see just fine. For tactical purposes of course, don't be sitting at the same place where the illumination is coming from.