Nikon 55mm f 1.2

Nikon 55mm f1.2

Problem: Fungus

The Nikon 55mm 1.2 and its two sisters the 50mm f1.2 and the 58mm f1.2 are the two fastest lenses for SLR by Nikon ever made. The Ai-S version of the 55mm is still sold new and there is no autofocus lens as fast for the Nikon system (for Canon there is the  perfect 50 F1.2L)

I actually got two similar lenses one from 1967 and one from 1971-72 (based on serial numbers). Both had few fungus stops on elements around the aperture.

This is actually quite an easy fix. The lens can be taken apart into two main assemblies: the focusing assembly and the optical one.

Fig 1 - The spot of fungus can be seen under "Nippon"

We start by removing the front ring. First you need to unscrew the small set screw in the side of the ring and than simply undo the ring (is stuck two tight, you can use the small screw as a lever and turn with a spanner - or something)

Fig 2 - The small set screw, just under the letter N in Nikkor-s

Ones the front ring is removed, you can simply take out the whole optical assembly. This is the time to point our that if you only want to get to the glass inside, or the front of the aperture, you don't need to take the whole thing out.

Fig 3 - Optical assembly is out.

Next the front element group can be unscrewed using a spanner and using it on the two grooves at the front of the lens. Having done this, one can clean the inner elements, As always, I use a Q-tip with some white vinegar on it to remove and kill the fungus. Next I use another Q-tip and clean the residue with some IPA and finally cleaning everything dry with some lens tissue or a cotton ball. 

Fig 4 - Clean.

The assembly is actually tricker if you need to put back the optics. You should align three things, the aperture lever, the auto (spring) lever and the slot and screw (screw on the side at the front of the opics). I found its easier to do with the stepped down, set the aperture ring to F16 and slowly get it in there - It will take few tries, and cries, but you'll get it in the end.   

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Rolleinar Zoom 80-200 f4

Rolleinar Zoom 80-200 f4

Problem: Aperture ring turns with no effect and some fungus

The name Rollei is most associated with the Rolleiflex TLR cameras, but there are few other cameras branded Rollei. First produced by the original German company, and later the production moved to Singapore. Rollei had a 35mm SLR line named Rolleiflex SL35. This Rolleinar lens is with the SL35 mount.

The lens I've got was in quite a good shape with it's original filter and lather case. The aperture ring turned but did nothing on the aperture itself. Pressing the "Auto" pin, the aperture would close to about F11 (or something) and thats it. No signs of oil on the blades. There were few marks of fungus on the inner elements I could remove on the way to there aperture.

Fig 1 - Rolleinar 80-200 f4. Most (if not all) were made by Mamiya (Japan)

Fig 2 - Hello there (fungus)

As we need to get to the Aperture mechanism we start from the lens mount. First you can remove the back lens assembly barral. Note there are two (in my case, can be more or less) spacer rings.

Fig 3 - View of the Rolleinar lens mount

Fig 5 - Unscrewing the back lens elements. The spacer rings are inside (see next figure)

 

Fig 6 - The two spacer rings.

First remove the 3 screws and remove the mount ring. Next you remove the rubber grip from the aperture ring so you can access the 3 screws holding the cover ring on the back. 

Fig 7 - Rubber grip removed from the aperture ring.

Ones the 3 side screws were removed, you can lift the cover ring from the back exposing 3 more screws holding the whole back end to the barrel.

Fig 8 - The cover ring removed. You can see one of the 3 screws holding the back at the top of the figure.

Now you can remove the whole back end with the aperture ring. Take care no to loose the bearing ball used to set the "clicks" for the aperture. My advice is to lift the aperture ring with a soft towel under the lens, this way ones the ball will drop (and it will), you won't have to look for it all over the room's floor.

Fig 9 - Aperture ring removed.

At this point I could figure out what was the problem. The coupling lever, coupling the aperture ring with the setting ring inside the lens was bent. So it didn't seat properly in the groove of the setting ring and turning the aperture ring did nothing. Removing the lever, it could be easily bend back to shape.

Fig 10 - The bent lever.

Fig 11 - And straight again.

At this point having access to the elements around the aperture, the fungus was removed. I used a cotton swab with few drops of white vinegar to remove and sterilize the lenses, next cleaned the residue with some alcohol and wiped clean with a dry swab. Putting everything back together is quite straightforward. Note only the coupling tab between the aperture ring and the inner brass ring. 

Fig 12 - The coupling tab

Fig 13 - The aperture can be set ones more.

Fig 14 - All done. Rolleiflex 80-200mm F4 - Repaired.

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Nikon 28mm f2.8 (AI-s)

Nikon 28mm f2.8 AI-s

Problem: stuck aperture and some fungus

The 28mm f2.8 Nikon lens is a solid build wide manual focus lens produced after 1981. This version is the last manual focus 28mm lens by Nikon. The lens uses a quite special optical design. More info you can find here: kenrockwell. This particular lens serial number puts it's date of birth somewhere at the late 80's or early 90's.

The lens had a stuck aperture and some fungus specs on on of the elements.

Fig 1 - Nikon 28mm 1:2.8 Ai-s with stuck aperture

So first we need to get to the aperture and. Most of the time the easiest way is by removing the mount and accessing the lens from the back.

Fig 2 - Nikon only used 3 screws on this version, well done Nikon. Note that only the mount screws need to be removed. Don't remove the black cover screws.

Fig 3 - The mount ring viewed from inside. This is a good time to wipe the "Auto" lever mechanism and remove any old dirt and grime.

Next you can remove the aperture ring assembly (the silver set ring, the stopper black ring and the aperture ring it self). Note the orientation of the silver set ring, as it can be placed back the other way around. Now you can also unscrew the back element groups. They all come out as a single piece which is great.

Fig 4a - Note the silver aperture setting  ring. The tab (on the right) should engage the slot in the plastic ring. The two screw heads connecting the tab to the ring should point inward.

Fig 4b - The "stopper" black ring with the stopper tab

Fig 4c - The aperture rings removed and the back lens groups removed. Now there is access to the aperture blades.

At this point you can close the aperture by moving the upright pin. Ones the aperture is closed oil can be removed by wiping it out with cotton swabs. I use White Gas as a solvent. Lighter fluid can also be used. 

At this point maybe you're lens is back working with a snappy aperture. If so, you can start to assemble it (In this case I believe in "don't fix what is not broken"). But in my case I needed to remove also the front lens assembly to clean the fungus, and clean the aperture blades from the front as well.

Move the focus to is minimum focus distance do the front barrel will extend and the tine set-screw can be visible. Remove the screw and now you can unscrew the whole front end (the filter ring).

  Fig 5 - With the barrel extended the holding set screw can be removed.

Fig 6 - With the front end removed, the front element group can be unscrewed.

Now we can simply unscrew by hand the front element group and clean it from inside (as I did to remove the fungus) and clean the aperture blades some more.

Fig 7 - The front element group - Cleaned. 

Fig 8 - Removing the old oil from the front of the aperture blades.

Thats it, at this point you can assemble back the lens tracking back the steps. Make sure you dust off the lens elements before screwing them back in. Remember, if you didn't tough the glass, most of the time you don't need to wipe it, just use some compressed air or a rubber blower to blow of dust. 

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