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View Full Version : Goerz Berlin DOPP-ANASTIGMAT Serie III DAGOR 480MM awakes from 25 year hibernation!



mohar
15-Mar-2010, 07:38
I have a Serie III Dagor that I would really like to turn into cash and would appreciate some pointers, especially an idea of what it might be worth and whether it is worth cleaning before selling it.

The lens came from what I think would be termed a banquet camera that I bought in Poona, India in about 1985 that was built by a german camera maker in Belgaum near Goa.

Unfortunately lack of luggage capacity meant I had to leave the stunningly gorgeous brass and teak camera behind when I returned to the UK and I am left with only the lens which has the following markings:
C.P. Goerz Berlin No 297530 DOPP-ANASTIGMAT Serie III DAGOR F=480MM 1:7,7

There are stop marks 8, 11, 16, 22, 32, 45, 64 on the barrel and a separate thin brass ring, the thread of which looks like it matches the thread on the barrel around the iris slot.
I assume that when no iris is fitted, this ring should serve to prevent dust etc getting inside.
To get the ring on, it would be necessary to unscrew the lens assembly which cannot be done by hand maybe because of oxidation on the thread.
Perhaps when the lens assembly is properly cleaned up it would be easy to unscrew.

The exterior lens surfaces look in good condition though could benefit from cleaning but the inside needs a good clean though I am wary about making an expensive mistake !
I thought I might first wash the inside out using a warm water detergent wash and then an isopropyl alcohol bath (if that would not dissolve the glue).

I must admit that though I could clean the lenses given the proper advice I am more inclined to sell for less and let the buyer do it though I would like to be absolutely sure that I don't miss any flaws that might make a buyer unhappy.

Any advice gratefully received !

Steven Tribe
15-Mar-2010, 12:42
Photos please!
A 480mm Dagor is a very large animal - which covers 22x25". There would certainly be a market amongst ULF folk. Threads can be a problem - I'm thinking about the climate of India with periods of very high humidity! If the front and rear lens cells are aluminium rather than brass you may have a problem which can't be solved as early aluminium corrodes/decomposes badly in contact with brass (copper/zink). Aprroximate value can be found by checking similar large dagors on ebay completed listings.

Don't try and clean anything yet!

mohar
15-Mar-2010, 13:44
Photos please!
A 480mm Dagor is a very large animal - which covers 22x25". There would certainly be a market amongst ULF folk. Threads can be a problem - I'm thinking about the climate of India with periods of very high humidity! If the front and rear lens cells are aluminium rather than brass you may have a problem which can't be solved as early aluminium corrodes/decomposes badly in contact with brass (copper/zink). Aprroximate value can be found by checking similar large dagors on ebay completed listings.

Don't try and clean anything yet!

I tried to post some images using the insert image button but it only gave the option to type in a URL rather than upload to the website. I see other posted images on this website so maybe I am missing something ?

While in India the lens had been kept with the camera in a large cedar wood box to reduce the effects of humidity I would guess and though there is no obvious visible corrosion, the end parts are not brass and I doubt it would take much to jam it as far as hand turning goes. For the last 25 years it has been in the back of a cupboard in England.

I haven't made a serious effort to unscrew it yet as I know it is quite valuable but if it was set up in a suitable jig and a little WD40 or similar was applied I would guess that it should unscrew ok.

Obviously at some point I will have to get some images posted, if not here then somewhere else.

Steven Tribe
15-Mar-2010, 16:44
When you start a reply - go first to "go advanced". At the bottom there is an attachment entry where can select images from your picture files. These must be quite small though - maximum file sizes are given.

mohar
16-Mar-2010, 03:21
When you start a reply - go first to "go advanced". At the bottom there is an attachment entry where can select images from your picture files. These must be quite small though - maximum file sizes are given.

I couldn't see any 'go advanced' option but maybe that is because we have different web browsers (mine is Firefox). I did find a paperclip icon though and uploaded 3 images. However I cannot find a way to attach these to a reply.

So I have uploaded 3 here. http://www.itsourcity.org.uk/temp/

Is this enough ?

eddie
16-Mar-2010, 03:32
hit post reply.

then down to manage attachments. then browse.

i sent you a PM with more ideas.

i took the liberty....

mohar
16-Mar-2010, 03:52
hit post reply.

then down to manage attachments. then browse.

i sent you a PM with more ideas.

i took the liberty....

I already tried as you suggested but after uploading the images then closing the window and returning to the message there was no indication that the images had in fact been attached to the message so I did not post it.

When trying to reply again and returning to manage attachments, there is no list of images that I have already uploaded.
I will just stick to putting the images on the other website for now but if you want to upload them here you are welcome.

What is a PM?

Steven Tribe
16-Mar-2010, 03:57
This is in good condition. Paint loss is endemic with aluminium bodied front and rear cells. The fact that the aperture ring has been removed means that something is seriously wrong with the iris mechanism (probably). This removal is not part of a usual clean and adjust servicing. Even is the iris has been removed or busted it is still of use as makeshift waterhouse stops could be used. Professional replacement/repair of the iris is both possible and expensive.

Some methods of loosening the cells are so extreme that I dare not mention them here where others read! However, the most reliable method I have used with big objectives is to attach two automobile oil filter wrenches to the barrel and the appropriate cell. Place on the floor and lock one wrench against the floor and apply torque on the cell with the other (anti-clockwise!). You have to make strips of cushioning/friction material to prevent metal to metal contact.

eddie
16-Mar-2010, 04:12
What is a PM?

private message. top right corner under your name.......

mohar
17-Mar-2010, 02:35
This is in good condition. Paint loss is endemic with aluminium bodied front and rear cells. The fact that the aperture ring has been removed means that something is seriously wrong with the iris mechanism (probably). This removal is not part of a usual clean and adjust servicing. Even is the iris has been removed or busted it is still of use as makeshift waterhouse stops could be used. Professional replacement/repair of the iris is both possible and expensive.

Some methods of loosening the cells are so extreme that I dare not mention them here where others read! However, the most reliable method I have used with big objectives is to attach two automobile oil filter wrenches to the barrel and the appropriate cell. Place on the floor and lock one wrench against the floor and apply torque on the cell with the other (anti-clockwise!). You have to make strips of cushioning/friction material to prevent metal to metal contact.


Thanks for this Steven. I never even realised it may be missing an iris until I took it out recently, at which point I realised the loose ring also belonged there. I would be happier if I could clean the internal lens surfaces before selling it but maybe the time and effort involved would make it impractical as I do not have appropriate tools to hand and would it be worth it in terms of what extra it might fetch on ebay for instance.

However, you say it looks in good condition so maybe it would not be as hard as I think and maybe careful application of WD40 or a similar lubricant would help. If I could fix it to something solid maybe I could even turn it by hand. I do have a rubber strip pipe wrench that might work (or not!?)

tonkhang
15-Mar-2011, 10:10
Can somebody estimate the value of this lens ? I try to find using Google but no I don't see any information.

John Schneider
15-Mar-2011, 22:36
I have rebuilt and recemented two of these magnificent monsters. To do this right you really should experiment with some worthless lenses before tackling this lens. Above all, go slowly and don't force anything without understanding how the parts are assembled.