My project today was to clean out the fungus growth inside my Nikkor 200mm AI lens. I never knew such a thing could happen, but it seems to be a common enough problem for many YouTube videos.

Anyway, I had to order a new set of screwdrivers to get the size (1.0 mm) for the tiny screw holding the forward barrel secure, so I could get to the back side of the front lens. That cleaned up easily. No etching of the glass or coating.

But, there is also a small amount of fungus growing in the inside of the rear elements. As I don’t have any tool available to loosen the ring holding the rear lens in place, I just left it alone. The fungus doesn’t seem to interfere with image quality as much as the front contamination did.

So, I call it 85% successful for a couple of hours work.