u/photonelecTR0NPHOTON

I live just outside a city and enjoy stargazing with NODs. I‘d read that IR pass filters can put a big dent in the effects of light pollution, and decided to give it a shot. As you can see, the effect is pretty dramatic.

IR pass filters work by reflecting wavelengths shorter than infrared, which means that most artificially generated light never makes it to the intensifier tube (mine actually allows some wavelengths of red to pass through as well, but it’s still effective).

I’m using this filter screwed into this thread adapter. Fortuitously, the adapter fits securely through friction inside the knurled plastic sleeve of the objective lens assembly on my Gen3 MUM-14. The filter can’t seat all the way into the adapter because it hits the inner threaded barrel of the objective assembly, but it’s secure enough for my use. If you want to use this filter on a PVS-14-pattern objective, I’m sure there’s a combination of adapters that will work.