Slightly OT - Contarex Lens Refurbishment

[dkCambridgeshire]

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In March 2007 I made an offer on a Contarex Bullseye camera outfit comprising Bullseye body (also known as Cyclops), 50mm f2 Planar, 35mm f4 Distagon, 85mm f2 Sonnar, 135mm f4 Sonnar and 21mm f4.5 Biogon plus two interchangeable film magazine backs c/w dark slides, bellows and filters. I offered less than one third the advertised price because all the lenses appeared to have the dreaded fungus and I was taking a chance that any of them would be capable of being cleaned/polished and recoated. At the time I was only interested in having the 21mm lens serviced and having it converted to a Leica M mount. The 21mm Biogon is a scarce and much sought after lens. Much to my surprise the dealer (London Camera Exchange in the Strand, London) accepted my low offer and I struggled home with outfit ... it was much heavier than anticipated. I then approached a specialist lens refurbishment company (whose name I'll not reveal for fear of embarrassing them) and much to my amazement they offered to give an estimate to clean/polish/recoat all the lenses (ie the glass lens elements) and also service the camera. The camera and lenses were sent to them, estimate received and agreed and thus began what turned out to be a very long wait for the jobs to be finished. Each time I chased them as the months went by the same excuse was given ie "Two of the lenses are totally jammed and we cant dismantle them". Eventually last September they advised that they could not service the jammed lenses but that the others were almost ready .... and the camera body service was finished but they could not source a replacement selenium meter cell for it. When I asked why the work had taken so long the technician replied, "I told you he died!" ... presumably he was referring to his colleague but he had not told me that. Last month I again chased them and was finally advised they would prepare an invoice which was received and paid last week. The following were thus received back last Friday.

 

Let's start with the jammed / fungused lenses which have not been serviced because they are jammed solid ie focusing rings are immovable. All the other lenses' elements looked like these when I bought them. But I have now discovered it is NOT fungus ... it is lens grease lubricant which has evaporated from the helicoil and condensed onto the glasses ... leaving a glue-like residue on the helicoil which has jammed solid . The grease originally used is peculiar to Zeiss Ikon in 1959/60 and has this property.

 

Thus this is the jammed 135mm Sonnar which cannot be serviced

 

And this is the same lens with the similarly jammed 35mm Distagon which also cannot be serviced

 

Now for the good news.

 

This is the beautiful and scarce 21mm f4.5 Biogon with its lens' surfaces repolished and recoated together with the dedicated 21mm viewfinder

 

 

And this is the same 21 mm f4.5 Biogon and viewfinder on the Cyclops camera ... the "Cyclops" eye is in fact the exposure meter. The lens mount is so long that it can only be used on the body with the mirror locked up ... hence the need for the viewfinder in the accessory shoe.

 

 

Continued ...

[dkCambridgeshire]

And here are the three lenses which have been successfully serviced ie dismantled, cleaned, polished and recoated - but not every lens element required recoating. The 50mm Planar was also showing signs of balsam separation so the elements were "split" and recemented using a special jig.

 

This shows the 85mm Sonnar on the Cyclops body

Note the 50mm and 85mm lenses do not have aperture rings. The lens diaphragm is coupled to a cam arrangement in the rear of the lens interior which is coupled and activated by the finger operated wheel behind the Contarex logo on the body.

 

Here is the 85mm Sonnar attached to the bellows. The bellows is actually made by Novoflex.

 

And here are two interchangeable film backs for the camera complete with dark slides. These enabled the use of different types of films with just one camera body.

The camera is fitted with an ordinary non-DS back at present but the DS magazines can be substituted enabling change of film "mid-roll".

 

The Contarex was and maybe still is the most complicated mechanical camera ever made and has over 1100 parts. Although popular in Germany in the early 60s it did not sell well partly because it was so expensive and heavy. Also, at that time the first Nikon F models began to dominate the professional 35mm camera market and they were cheaper, more reliable and offered a more comprehensive system ie more lenses and accessories.

 

However, some authorities maintain that the quality of Zeiss Contarex lenses has never been surpassed both optically and mechanically.

 

I'm looking forward to using the camera soon and may obtain a Contarex to 4/3 adaptor thus enabling use of the 50mm, and 85mm lenses on a 4/3 digital body. I think the 21mm lens will be too long to adapt for digital use.

 

Two years was a long time to wait but just to have the 21mm lens has been worth the wait.

 

Total cost for the work was £266.80.

 

Cheers

 

dunk

Edited March 16, 2009 by dkpeterborough

[k_g_wolf ✝]

Great story and thx for sharing. Enjoy your "new" outfit.

 

I handled one these cylopes recently but hesitated to get it because

of the cla which it needed. Sometimes we must be able to give things up.

 

Good you didn´t, the refurbished pieces look like new !

 

 

Best

[Theodor Heinrichsohn]

Dunk,

The 21/4.5 and the finder are worth more than you paid. As I purchased this lense many years ago in Japan (converted to Leica screw mount) and have used it on my older Leicas as well as film M's and now the M8, I greatly appreciate the quality.

Congratulations on your purchase.

Teddy

[dkCambridgeshire]

Dunk,

The 21/4.5 and the finder are worth more than you paid. As I purchased this lense many years ago in Japan (converted to Leica screw mount) and have used it on my older Leicas as well as film M's and now the M8, I greatly appreciate the quality.

Congratulations on your purchase.

Teddy

 

Also have this Minolta 21mm f4.5 W Rokkor lens (copy of the Zeiss?) but do not yet have a "mirror up" Minolta camera to try it with. Will be interesting to compare the Minolta's results with those of the Zeiss 21mm f4.5 Biogon . The Minolta dates from the early 60s.

 

 

Cheers

 

dunk

Edited March 16, 2009 by dkpeterborough

[luigi bertolotti]

Happy to see this gear... Contarex is the ONLY 35mm SLR I used extensively: my one is a Super model II (i.e., with lever-actuated meter), a bulky fantastic chrome body, with proper black eveready bag which by itself weights not so far from my Rollei 35... the leather's thickness surpasses some good mountain boots, and the bottom is also reinforced, I think, with some metal blade inside..

Body was CLAed by W.Rentsch in Mailand,only issue is the meter.. it works fine but the battery has a duration of some DAYS... I suppose there is something in the circuitry that drains current away... but preferred to keep it as is: when using such a heavy gear, a decent handmeter is a negligible add-on.

Lens set is very complete: 25 f2,8, 35 f4, 50 f2, 85 f2, 135 f4 plus two jewels worth a specific mention :

- Distagon 18 f4 (superclean, complete, case...) : is true that my experience is limited to Leica 21s and CV 15... but I wonder if is possible to design a better WA... it simply DOES NOT vignette, even wide open, DOES NOT distorce lines, even making trivial tests at 1 meter with a squared sheet of paper, it has a crispness at angles that simply CANNOT BE DISTINGUISHED from center image. Unfortunately... it's not made like the Biogon... ... it has the standard complex coupling with diaphragm setting ring on the body... I fear is almost at all impossible to have it converted/ring-adapted to M mount. I'd like to have or at least to test the new Leica 18 f 3,8... and the first thing I dream to do is mounting it on a M film camera and make a comparision with the Distagon: with all my Leica passion in account... I would be surprised if the Distagon would show something less in image quality.

 

- Olympia Sonnar 250 f4 : 2nd version with removable grip and quick focusing system : this, in itself, is a typical Zeiss cervellotic invention, frankly inpractical in use... but the lens quality is astonishing... with distant subjects, I have always had the feeling that it has "something" that makes the density of atmosphere to magically disappear. And, removing the handgrip and using the focusing wheel you enjoy a smoothness and precision of focus that is incredible: pity that the standard focusing screen I have is not so bright... with subjects in shadow, the focusing tends to be difficult. One of the funny details is that its solid leather case is locked with a tiny key... ridicolous to think it can be seen as a anti-thief protection...

 

Me too have the bellows above depicted... one day I wondered if removing from it its diaphragm ring, then machining a 2nd ring to couple with it and with a M mount at the other end, it could be possible to have a Frankestein M adapter for my 18... too risky and difficult to engineer...

Edited March 16, 2009 by luigi bertolotti

[dkCambridgeshire]

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Luigi, There are 4/3 adaptors available for the Contarex lenses so maybe it might be possible to mount your 18mm Distagon onto a 4/3 or micro 4/3 digital body and maybe then compare its digital image with that of the new Leica 18mm adapted for the micro 4/3 Panasonic G1?

 

Cheers

 

dunk

[luigi bertolotti]

Luigi, There are 4/3 adaptors available for the Contarex lenses so maybe it might be possible to mount your 18mm Distagon onto a 4/3 or micro 4/3 digital body and maybe then compare its digital image with that of the new Leica 18mm adapted for the micro 4/3 Panasonic G1?

 

Cheers

 

dunk

 

Adapters for Contarex lenses on 4/3 ? Where can I find some info about ? Not that I think to buy one (haven't a 4/3 body... and 18=36 in 4/3 FOV...) but I am curios to see how such an adapter allows to set f/stops on a Contarex lens (supposed it can...).

[dkCambridgeshire]

Adapters for Contarex lenses on 4/3 ? Where can I find some info about ? Not that I think to buy one (haven't a 4/3 body... and 18=36 in 4/3 FOV...) but I am curios to see how such an adapter allows to set f/stops on a Contarex lens (supposed it can...).

 

Mods do not like links to sellers but ...

 

If you do a search on Ebay just using "Contarex" details of the adaptor available in HK should come up within the list ... and it has the finger wheel.

 

Cheers

 

dunk

[luigi bertolotti]

Well... I searched and found this manufacturer in Italy...

 

Negozio eBay - COMA Costruzioni Ottiche Meccaniche: Fotografia Photo, Astronomia Astronomy, Ottica Optics

 

who displays THIS :

 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

 

You bet I'll call him... seems the aperture issue is smartly managed... and with a 18 f4 one can even forget the RF coupling...

[dkCambridgeshire]

Good news! I had not seen that one. It will be investigated. There is also the Contarex to 4/3 adaptor in Hong Kong which should allow the Leica Digilux 3 to use Contarex lenses. I wonder if Leica was fully aware of the implications of signing up to the 4/3 partnership?

 

Thanks

 

dunk

[rickp13]

dunk

 

several gold stars to you for patience and perserverance. the photos and story are very interesting!

 

cheers

 

rick

[dkCambridgeshire]

Well... I searched and found this manufacturer in Italy...

 

Negozio eBay - COMA Costruzioni Ottiche Meccaniche: Fotografia Photo, Astronomia Astronomy, Ottica Optics

 

who displays THIS :

 

[ATTACH]131945[/ATTACH]

 

You bet I'll call him... seems the aperture issue is smartly managed... and with a 18 f4 one can even forget the RF coupling...

 

Does this just bayonet onto the existing Contarex mount or does it replace part of the Contarex mount ... i.e. if the latter does the Contarex mount require disassembly?

 

Cheers

 

dunk

[luigi bertolotti]

Does this just bayonet onto the existing Contarex mount or does it replace part of the Contarex mount ... i.e. if the latter does the Contarex mount require disassembly?

 

Cheers

 

dunk

 

I plan to call them TODAY in the afternoon... the site states they can be called from 16 to 17 h only (and they are italians like me...), so I think I'll have some more info... looking at the small pic, my idea is that you haven't to dismount anything from a std. Contarex lens...the aperture ring probably moves a small lever that actuates the small lever internal to Contarex' lens mount, which normally is engaged via the complex automatic diaphragm setting mechanism initiated by the presetting ring that is in front of the Contarex body; I have always thought that Zeiss invented such a complicated mechanism for, this way, you had, on the other end, a very simple way to couple to the Cyclope front selenium meter... when they switched to TTL, of course a simpler system could be engineered... but almost all the lens set was already designed for that coupling system...

Edited March 18, 2009 by luigi bertolotti

[luigi bertolotti]

I called them and ordered one today... seems to be a good lab... they confirmed me that diaphragm is completely manegeable, and there is NO RF coupling (but I considered this rather obvious, given the price and the structure of Contarex lenses); can be I'll have this strange ring in 4-5 days, and am very curios to test my beloved Distagon 18 on it... , pity it will be probably the only usable lens : maybe the 25... decently closed and at not too near distances, and 250 for some infinity shot...

 

I'm already wondering how to manage (in case it proves to be a good solution) the UVIR filter issue... Distagon 18, fortunately, had not the "proprietary" Zeiss bayonet mount but a 67mm thread which was at risk of vignetting, so there was also a 96 mm thread onto an accessory ring... I see that BW pricelist includes a UVIR 67mm of the "slim" type, and of course with M8 the risk of vignetting caused by filter mount is reduced... but I wonder if the 67mm thread of the Distagon is a std. 0,75 pitch as BW... Zeiss was famous to make oddities... I'll try to check with a caliper...

Edited March 19, 2009 by luigi bertolotti

[dkCambridgeshire]

I succeeded in dismantling the jammed 135mm lens. Thus the main part of the jammed focusing mount minus lens module and diaphragm module can now be soaked on Ronsonol lighter fluid to try and dissolve the solidified grease. This will be achieved by immersing the aluminium mount in a Pyrex dish full of Ronsonol and sealing it with a plastic bag and rubber band to prevent evaporation - and will be left outside in the garden to soak for a couple of days because of the fire risk indoors.

 

The residual oil has condensed on the rear of the front lens element(s) and looks as if it will clean off if the module can be dismantled. But if the front elements are cemented together and the oil has penetrated the cement the cleaning might not be be possible ... I'm in unknown territory. It is possible to split cemented elements but they will require soaking in acetone for days ... or heating. Will let you know how the project progresses.

 

These are the main components after dismantling. In the first picture the diaphragm module on the left is very clean and the diaphragm operates smoothly. The focusing mount ie the lens barrel at the rear has a completely jammed focusing ring.

 

 

The front lens element(s) in the module show the condensed oil deposits

 

Now have to try and dismantle the actual lens module which comprises several glass elements in their housing and am awaiting advice as to how to proceed.

 

cont'd

[dkCambridgeshire]

The rear lens elements are quite clean

 

When the lens was away for service no work was done on it because of the jammed mount. Will be a good achievement if I can succeed where they did not. Interesting learning process too.

 

Cheers

 

dunk

[dkCambridgeshire]

After extracting front element "A" with a suction cup, the anulus surrounding elements "B" and "C" twisted off ... here are the components ... the fourth lens element is in the rear of the diaphragm tube and it is quite clean

 

 

Close up of the module comprising elements "B" and "C" together with the anulus which twisted off with firm finger/thumb pressure. The join between "B" and 'C" is just about visible.

Now I have to 'split' the above elements "B" and "C" so as to clean the oil spots which have penetrated the cement

 

Close-up of the front of lens element "B" showing the oil stains in the cement between element "B" and "C"

 

Splitting lens elements is something I have not attempted previously but seem to recall that the cement can be softened using acetone ie nail varnish remover ... but it takes days to penetrate.

 

Reading Thomas Tomosy's "Camera Repairs and Maintenance" books he advocates separation by heating the elements with a hair drier for about an hour after fabricating an enclosure to keep the heat in. So will try this method and hope it works ... but it may not work if the cement is not Canada balsam. However, vintage Contarex lenses are so prone to balsam faults that it seems likely that Canada balsam was in use in the mid 50s.

 

Once the elements are apart it should be possible to clean the residule cement and the oil stains using acetone and then re-cement them together. But maybe these are not oil stains ... could they be balsam separation?

 

I think Surplus Shed sells optical cement ... maybe not the same refractive index as Zeiss' original cement but maybe it will do the job.

 

This lens was going to be trashed but maybe it can be salvaged ... if the lens elements come apart and clean up ok then just have the focusing mount to free-up ... have not started the focusing mount soak yet.

 

Cheers

 

dunk

[dkCambridgeshire]

... . The join between "B" and 'C" is just about visible.

Now I have to 'split' the above elements "B" and "C" so as to clean the oil spots which have penetrated the cement

 

 

Error on my part ... the join is not visible ... the join is at the waist of the outer metal sheath supporting the two elements ... diagram here

 

Cheers

 

dunk

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Hallo,

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[wizard]

But maybe these are not oil stains ... could they be balsam separation?

 

Yes, that's what I would think, balsam separation. No need for a new optical element. Once you have removed the old layer of Canada balsam and cleaned the lens sufaces, you could recement them together using a modern 'glue'. How to do this without entrapping air bubbles is another matter...

 

To separate the two elements, I would put them in an oven and heat them up slowly, starting at 50 or 60 Celsius. If that isn't enough, raise the temperature in 10 degree intarvals. And beware when taking the elements out, they will be hot!

 

Cheers,

 

Andy