Скачать или смотреть DIY Night Vision Iris Focus Device - Type 2

This is the Type 2 DIY Iris. For the Type 1 DIY Iris, please see the video here:
   • DIY Night Vision Iris Focus Device - Type 1  

This is the basic tutorial for how to make a DIY Focus Device for NVGs, using common parts. This version uses a modified NVG rubber eyecup to mount the iris. Not necessarily a better solution than Type 1 DIY Focus Device I previously made a tutorial for, just different. One benefit to this method is that it's easier to re-index the Iris according to your orientation needs. The other benefit being that you can mount an easily replaceable sacrificial lens to the assembly.

This video is for informational purposes only. It is NOT monetized.
This is not the only method to make a DIY Focus Device, simply one I learned from an IG friend, "Fizzii".
I take no responsibility for any damage your Night Vision Device incurs.

Aperture / Iris Device for NVGs
A cap or cover that's mounted to the front (objective) lens and functions much the same way the aperture setting on a camera works: the smaller the opening the greater the depth of field, thus eliminating objective lens refocusing. Rather than your Night Vision Device having a standard 10-20 yards to infinity focus, with the refocus device it can now have a 12" to infinity focus. This is of course at the cost of a reduction in the amount of incoming light entering the night vision device. Most modern autogated NVGs will adjust for that reduction in light and pump up the output signal. However, reduce it too much (e.g. a pinhole) and the signal noise increases dramatically.

It's about finding a balance.