Leica Summarit 50mm f1.5

Leica Summarit 50mm f1.5

Problem: Heavy haze on elements

A lot has been written about the Summarit lens. It was manufactured for 18 years (1939-1957 - Actually no lens were manufactured during WWII so its less than 18 years) with total of just under 75K copies made. A good place to read about the lens is here: slrlensreview.com.

The copy I've got dates back to 1954 and had a heavy haze on the elements around the aperture. This actually quite common in my experience with Leica lenses. The haze is an oily residue coming from the grease and lubricants evaporating and landing on the elements adjacent to the aperture. 8 out 10 times (not a real statistics) you can get it of with some alcohol.

Fig 1 - The Subject.

Fig 2 - Its kinda hard to see, but there is a lot of haze in there.

So now we know the problem, we need to get to the elements. The strategy, as in most cases will be to remove the back elements group. Most of Leica lenses I came across have to main assemblies, the focusing assembly and the optics+aperture assembly. As you can not remove the back elements without removing some parts of the focus assembly - the disassembly begins.

NOTE: I started with no references and just removed all the screws - This is not the right think to do. So ready the text because the photos can have some unnecessary stages.

(Don't do this step) - The first obvious screws are the three flat heads on the lens mount. I started by removing them and unscrewing the lens mount. With this done you actually removed a main part of the focusing mechanism, which means you'll have to assemble it just right later on.

Fig 3 - The three flat heads on the lens mount (don't remove)

Fig 4 - The lens mount removed, you still can't get to the retainer ring of the back element. So actually it got us nowhere.

The next screws in line are two screws on the focusing ring. You can remove only one of them.
Next are three set screws between the focusing and the aperture ring. You need to remove all three screws. Thats it. Don't touch the screws on the aperture ring.

Fig 5 - More screws. Note the mount ring should be on (didn't I say it already?!)

Now we get to the tricky part. At this point the optical assembly will turn freely, but that it, you can ture it for ever and nothing will happen.
What you need to do is to take a pin or fine screwdriver (it should be something sturdy, not a paper clip). You insert the pin into the one screw hole you opened on the focusing ring. The pin should enter into a hole in the inner ring that you can't see. But you can feel it, or if you look closely you can actually see it thru the hole.
Now the optical assembly can't turn and you can unscrew it. Yes, it is screwed hard(!). Try not to use the aperture ring for grip. There are actually tabs at the front of the lens, use them (with a spanner or something)

Fig 6 - The pin in the hole. You can see the tab on the front

Fig 7 - This is what we want to end up with

Fig 8 - The focusing assembly. The screwdriver I used as a pin is still in place.

From here on it's very straight. Unscrewing the outer retainer ring you need to remove 3 elements. Note that they are placed in a very tight fit (I'd like to see the tolerances on that machining drawing). So you need be patient removing the elements. 

Fig 9 - First element out

Fig 10 - All three out, the innermost element is on the left.

Thats it, now you have the aperture. Clean it. Open it and clean the element and the elements you removed and just assemble everything back.

Fig 11 - The aperture wide open (well closed, but you get the idea).

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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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Minolta Rokkor 58mm f1.2

Minolta Rokkor 58mm F1.2
Problem: Stuck Aperture

Got this lovely lens by Minolta made between 1969 to 1973. This is the 2nd version of this lens which is all metal and really feels like a tank. More info can be found here: rokkorfiles

The glass was in very nice condition and the focusing was quite smooth, but the aperture was stuck wide open. Rotating the aperture ring or moving the "Auto" lever on the back had no effect.

  Fig 1 - The Rokkor PG f=58mm 1:1.2

Fig 2 - The aperture stuck open

9 out of 10 of the times (not really a based statistics) is that degraded oil or grease from the focus helicoil drifted along the years to the aperture blades and/or the aperture opening levers and springs making them stick. So we need to get to the aperture mechanism.

First remove the bayonet. (Fig 3) Note there are 8 screws, 4 short ones and 4 long ones. You really need to remove only the long ones. Removing all of the screws will make your life a bit more difficult (as was mine).

Fig 3 - Unscrewing the back mount ring

If you did remove all the screws, by accident, or on purpose to clean the "Auto" lever ring, you will find a set of 5 small (very small) bearing balls and a set of 5 spacer segments. Take care so not to loos them on the ground, on the table or even in the lens it self. (Fig 4)

Fig 4 - Note the small bearing balls (3 out of 5 shown) and the spacer "rods" between the black ring and silver mount ring.

Ones the whole back mount assembly (mount, "Auto" ring and base ring) are removed, you can remove the aperture ring (Fig 5). Note that if you only want to clean the aperture blades, and the ring turns fine you don't have to remove it. If you do remove it, note how it is placed: in the ring there is a protruding slotted lever that should be engaged into the angled lever on the lower "golden" stopper ring. (I don't have a photo of it).

Fig 5 - Aperture ring

Fig 6 - Aperture ring removed

If you do decide to remove the aperture ring, take care not to loose the small bearing ball used for setting the "clicks" of the aperture. It is located under the ring where you see a set of grooves (Fig 5 - under my index finger).

 Fig 7a - Note the small ball sitting on top of a spring inside a drilled hole

Fig 7b - The ball removed you can see the hole with the spring inside.

If you do remove the ring and the ball falls, you can hold it back in place by putting a small drop of oil or a tiny dot of grease on it so it will "stick" into the hole.

We are almost there, only left with removing the back lens elements. There are to groups both can be unscrewed quite easily. As always try not to touch the glass it self. Ones the two groups are removed, you can screw them together so less dast will setter. Later you can screw them back in together. (You can be lucky and remove the whole assembly of the two groups as one part).

Fig 8 - Back lens assemblies removed.

Now we are at the aperture level. First you need to close the blades. There is a upright pin you can play with (no pun intended) few times and the blades will close. For cleaning I use White Gas, but lighter fluid should be fine as well. Drop a few drops on the closed aperture, and wipe. Repeat few times. You will see the old oil being dissolved by the gas and picked up by the cotton stick. Next drop few more drops and play with the aperture so the gas will get on to all the blades. Not drown the thin in gas. I use a syringe to drop 2-3 drops at a time.
You should also clean around the barrel where the levers are.

Fig 9 - Removing oil from the blades.

Ones you are happy with the result (it can be a good idea to level the lens in a worm room for a day, so more old oil will flow and will be removed) you just track back the steps and assemble the lens. If you did remove all 8 back screws, it can be smart to first assemble the back rings so you don't have to mess with the small spacers and balls.

Fig 10 - The back ring assembly. This is what you should end up with if you don't removed all 8 screws. 

Fig 11 - Don't you just love a snappy aperture?!

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