Repair: Nikon PN-11 Extension Tube


The PN-11 extension tube is a companion accessory to the amazing, popular and very long-lived Micro-Nikkor 105mm f/2.8 Ai-S lens. This lens was introduced in the early ’80s but it’s still in production up to this day. Having said that, the PN-11 is obviously in-production as well. You have to buy the PN-11 separately which doesn’t make sense since it is so vital to the Micro-Nikkor 105mm f/2.8 Ai-S’s performance and it is needed for the lens to achieve a 1:1 (almost) reproductive ratio. Why Nikon sold these separately, I don’t know.

Here are pictures of the PN-11.

Repair: Zoom-Nikkor 43-86mm f/3.5 (2/3)

Hello, everybody! Sorry for the irregular blog updates as I am very busy this month. We are scheduled to have a lens teardown this time but I am too busy to write a full teardown so I am going to continue a previous series that I started many months ago. This is supposed to be just a supplement of the first part so I will keep this short.


The Zoom-Nikkor 43-86mm f/3.5 lens that I discussed previously is an important lens in the photography world because it was the first affordable (normal range) zoom lens for the 35mm format. As I mentioned in the previous part, the lens had some quirks that needed to be ironed out and some of it was corrected in this version with the addition of a modern lens coating – the Zoom-Nikkor C 43-86mm f/3.5 lens.

img_1115The lens balances wonderfully on the Nikon D750. I had to convert this lens to Ai before I attach this to the Nikon D750 or else the lens will damage the camera’s Ai coupling tab. More

Mod: Alternative Ai Conversion Method

Hello, everybody! I haven’t updated anything for a weeks now and it looks like it’s going to be that way for the rest of this month. I am currently very busy with visiting family and a friend who also happens to be my dog food supplier. I will resume our normal schedule on November when things slow down a bit, until then please enjoy this little article.


Some earlier Nikkors have a thin aperture enough ring that doesn’t even touch the aperture coupling tab of modern Nikon cameras. Converting these to Ai is much easier compared to the ones that have a thicker aperture ring wherein you need to grind off any material that is in the way of the tab.

Today, I will show you how I make these lenses work with any Ai interface so that you can enjoy these old lenses with your modern Nikon cameras and get aperture priority metering with it.

img_1339The Nikkor-H 50mm f/2 is one such lens. This is an easy mod since the tab needed for this is not as big as the ones needed for slower lenses. More