Slightly OT - Contarex Lens Refurbishment

[dkCambridgeshire]

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Thanks Andy ... will try and separate the elements asap.

 

Cheers

 

dunk

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[dkCambridgeshire]

Managed to source and purchase metal lens hoods ie 50-135mm and 21-35mm

 

Fitted to the 85mm f2 Sonnar

 

Fitted to the 21mm Biogon

 

Had opportunity to buy a Contarex 85-250mm f4 zoom last week but declined - partly because was expensive but also because is a massive lens, very heavy (2.7Kg plus weight of its case) and would have no real use for it. The asking price was £700 which was quite reasonable considering its rarity ... only 581 were made c. 1966 and was one of the very first quality zoom lenses "made to the same performance standards applied to fixed focal length lenses" ( Zeiss Compendium, Barringer and Small)

 

Cheers

 

dunk

Edited April 2, 2009 by dkpeterborough

[dkCambridgeshire]

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...

 

Did the adaptor arrive Luigi and if so is it working well?

 

Cheers

 

dunk

[thrid]

Hey, this is a great project.

 

Have you considered how your will properly center the two elements when you glue them back together?

The prformance of the lens will be highly dependent on getting this step correct...

 

Maybe you can have a shop with the proper gear reassemble everything for your.

 

You could try this fellow

 

The Zeiss Ikon Contax Camera Home

 

Or check with a cine camera technician / rental house. There are a lot of custom lens modifications done in that business.

[dkCambridgeshire]

Hey, this is a great project.

 

Have you considered how your will properly center the two elements when you glue them back together?

The prformance of the lens will be highly dependent on getting this step correct...

 

Maybe you can have a shop with the proper gear reassemble everything for your.

 

You could try this fellow

 

The Zeiss Ikon Contax Camera Home

 

Or check with a cine camera technician / rental house. There are a lot of custom lens modifications done in that business.

 

Thanks, I had already seen the Contax link and a very similar Contarex link written by the same author. If you look at the module housing the two elements requiring separation, the metal outer enclosing same is a perfect fit around the tapering front element - thus when the elements are cemented back together they should meet in perfect alignment.

 

Cheers

 

dunk

[thrid]

If you look at the module housing the two elements requiring separation, the metal outer enclosing same is a perfect fit around the tapering front element - thus when the elements are cemented back together they should meet in perfect alignment.

 

I took a Olympia 2.8/180 apart a few years ago and it had a similar setup, but we are talking about tolerances here that you can't see with the naked eye...

 

Maybe you could shoot Henry an email and ask him if it's an issue. He's very helpful with information.

[luigi bertolotti]

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Did the adaptor arrive Luigi and if so is it working well?

 

Cheers

 

dunk

 

Yes, arrived and WORKS FINE, even if its build quality is not at the top, but I tested my Distagon 18 with great satisfaction... I'm thinking seriously to buy an UVIR for it, a 24 (or 25) mm finder and consider it as part of my std. M8 lens set...

I've posted some test pics ina pair of threads... "Guess which lens is this ?" and "18mm lenses for Leica M", both in the M8 subforum: I'm really excited by the quality of my old Distagon !

[Guest flatfour]

The Contarex was a superb camera - built too well for the price, and the lenses are probably the best that have ever been made. That said it is a colossus of a camera; very heavy. The pictures are pin sharp if the lenses are in good order but they are very heavy. I have kept mine as it is such a marvellous piece of engineering and optical perfection.

[dkCambridgeshire]

Yes, arrived and WORKS FINE, even if its build quality is not at the top, but I tested my Distagon 18 with great satisfaction... I'm thinking seriously to buy an UVIR for it, a 24 (or 25) mm finder and consider it as part of my std. M8 lens set...

I've posted some test pics ina pair of threads... "Guess which lens is this ?" and "18mm lenses for Leica M", both in the M8 subforum: I'm really excited by the quality of my old Distagon !

 

Thanks Luigi, I will order one ... can you please confirm the supplier is not in the earthquake zone.

 

Cheers

 

dunk

[thrid]

Here's an interesting article on Contarex lenses

 

Contarex lenses

[luigi bertolotti]

Thanks Luigi, I will order one ... can you please confirm the supplier is not in the earthquake zone.

 

Cheers

 

dunk

 

Hmmm... the supplier is in TERAMO, which really isn't so far from the tragic earthquake area... if you look at a map of central Italy, you easily spot L'Aquila (heavily damaged yesterday night), and going eastward you find Teramo, divided from L'Aquila by the important massif of Gran Sasso, i.e. from the other side of Appennini, the mountains chain that divides all the central-south part of Italy. Send them a mail and wait for an answer...

[dkCambridgeshire]

Hmmm... the supplier is in TERAMO, which really isn't so far from the tragic earthquake area... if you look at a map of central Italy, you easily spot L'Aquila (heavily damaged yesterday night), and going eastward you find Teramo, divided from L'Aquila by the important massif of Gran Sasso, i.e. from the other side of Appennini, the mountains chain that divides all the central-south part of Italy. Send them a mail and wait for an answer...

 

 

Thank you Luigi

 

Cheers

 

dunk

[yunier]

Quote

The 50mm Planar was also showing signs of balsam separation so the elements were "split" and recemented using a special jig.

Hello! Can you help me by saying how you managed to separate the elements? I have a 50mm spaced Planar that I would love to repair.
Cheers!

[jerzy]

reading through the thread now I have remarks regarding separating elements:

- do not use acton, use denaturated alcohol to clean elements from the remainings of canada balsam. In case when elements are cemented with modern glue (UV hardend) it soaks the aceton, incerases its volume and especially thinner elements will break. You can use aceton to wash up remainings of UV glue after elements are separated

- best method for separation is heat, canada balsam needs temperature of 100-120C, UV glue needs approx 200C. Use gloves to separate elements then by shifting one element sideways. Both heating and calming shall be done in a "soft" way - when heating put it in cold oven and heat up, when calming after separation put again in warm oven and let it calm together
'Very often lens makers  (like Leitz) however mount cemented elements in brass mount in the way that you need to lathe off a bit of brass to be able to remove the elements

[ph.]

Most adventurous undertaking!

I suspected that the stuck helix was caused by aluminium to aluminium "welding" which occurs with some filters and does not respond to penetrating oil- which I would hesistate to  use on a lens.

 

Recently I have succesfully battled another Zeiss grease-glue isssue. I aquired a Zeiss standard microscope with photo tube and all relevant optics plus a contarex microscope camera cheaply since the condenser adjustment  was stuck solid. Since I have less inhibitions ad disassembling "coarse"mechanics than micron precision optics, I detatched the adjustable table and the condenser movement device, cooled it to -20 then heated it to +50. The shock treatment freed up the solidified grease enough so that I could turn the adjustment wheel and clean the rails everything slid on.The next step will be to adapt a digital camera to the photo tube.

I do not suggest similar treatment for stuck lenses, but a slow heating might loosen the intractable gluegrease.

p.

 

[Stacey]

Sometimes an ultrasonic cleaner helps with stuck lenses. On using these symmetrical ultra wides on digital, most will disappoint as the ray angles don't play well with most digital sensors.