View Full Version : Balsam or Synthetic in This '67 Lanthar

Richard K.
28-May-2010, 13:17
I acquired an otherwise beautiful 30 cm Apo-Lanthar today but it does have some separation- about 1/4 of the way around the front up to around 5 mm wide; there is some starting on the rear as well. Very hard to show the extent of it in a photo because it depends on viewing angle. Can a knowledgeable person tell me if it's fixable or does that depend on the cement type, Canadian balsam or Synthetic? Will it continue to deteriorate or can it be used as a user. Has its value to a collector gone to zero? If it cost say $1500, what would the value now be? I may return it since it was significantly not as described but I also thought that if enough money was refunded me,it might be OK to keep it. But at what refund level? Thanks for your thoughts!

Here is a poor photo of the separation:


28-May-2010, 14:35
1. Are you sure it is separation? Going by the image it looks more like Schneideritis (i.e. edge paint peeling off).

2. Zeiss had already gone over to synthetic glues before WWII, and Schneider and Voigtländer followed them rather soon - a top rank lens formulated in the fifties and made ten to twenty years later will positively have been glued with synthetics. The more interesting question would be which synthetic? By the seventies UV curing acrylic had become standard, but older designs still were glued with epoxy. While it is not impossible to separate acrylic glued lenses with solvents, epoxy is far more resilient...

3. The collectors value is near zero, unless you fake it up and don't get caught. I have my doubt whether they have a real collectors value, though - "collecting" Apo-Lanthars seems to be more of a preoccupation of vanity users. And the use value did not lose that much...


Richard K.
28-May-2010, 14:45
1. Are you sure it is separation?

What looks like just a reflection starting just to the right of the G in Braunschweig and running under TECH is separation. I've also had it confirmed by my local repair ship when I took it in to be mounted on a board.

Dan Fromm
28-May-2010, 15:05
Sevo, Newton's rings are a consequence of separation. Schneideritis is due to separation of the black anti-flare paint from the edges of the glasses. Often looks like bubbles at, always, the edges, not between the elements.

Richard, it is almost certainly synthetic cement. I have some Apo Skopars of the same vintage that are horribly separated.

Before you give up on the lens, shoot it and see how it does. It may surprise you. Its not badly separated, nothing like my absolutely horrible 58/5.6 Grandagon, which has a ring of fire in the front cell and silver spots in the rear. But, y'know, the wretched thing doesn't shoot badly.

Repair is possible, ask John Van Stelten of Focal Point for an estimate.

Richard K.
28-May-2010, 16:55
Repair is possible, ask John Van Stelten of Focal Point for an estimate.

Think I will do that. Thanks Dan! BTW, if left alone will it continue to worsen?

Dan Fromm
29-May-2010, 05:26
Richard, I have no idea whether your lens' separations will grow. They've grown, but ...

8x10 user
29-May-2010, 12:36
Its worthless now... You should just send it to me ;)

Michael Jones
1-Jun-2010, 08:06
I had a gold dot dagor with nearly identical seperation. the area never grew nor did it have an impact on the image.