A little technology

Repair is a profession...

It's also a passion


The purpose of this short article is to show that...

Nikkor 300mm f/2.8 AI

A mythical lens

This 300mm was a deal with a friend.

The reputation of this optic is not overrated, I didn’t hesitate!

A violent impact had twisted the bayonet, separated the return spring support from the diaphragm and twisted the closing cam.

The diaphragm ring was also twisted, the lamellae loose.

The risk that this optic was completely unrecoverable was significant, with no evidence of the internal state of the lenses.

Upon dismantling, it turned out that the bayonet mount support had not suffered any trauma, no screws bent (lucky).

Dismantling the barrel does not pose any difficulty in reaching the diaphragm.

This one dismantled, the spring support was only simply loosened.
A little trickery, and this piece was set securely again. Correctly replaced, the slats and the diaphragm were functional.

The trickiest part was the bayonet. Luckily again, I had an 85mm f/2 without an optical unit, a real organ donor.

Luckily again, the positions of the 85mm fixing screws were identical to the defunct bayonet.

With the diaphragm closing cam straightened, it was easy to raise the rear of this 300mm.

There could have been a difference in the thickness of the bayonets, although this was particularly standardized.

The diaphragm ring, even twisted, still allowed it to be used as is.

Luckily again, on this original lens, the focus exceeds infinity, which could compensate for a possible difference in draw.

The lenses were in good condition and appeared to have suffered no damage.

All that remained was to test it “the moment of truth”!

Mounted on a D3s, what was my surprise to find that this 300mm was really excellent!

Its used aesthetic full of charm implied that “he had seen it”, no matter, it works and particularly well.

– Test photos were taken only at wide aperture –

I decline all responsibility if you damage your toys !!! There are professionals to do this work !

Nothing is totally impossible