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View Full Version : Voigtländer Braunschweig technika-heliar 1:4,5 / 21cm



Anders Korhonen
10-Mar-2010, 06:01
I just scored this lens in a trade to 35mm system and some money, The optics are clean, apart from some dust and small hairs, the compound is in equally good crisp condition and has had maintenance done to it a month ago and has a 6 month guarantee. However, now that I examined the lens more, it seems that it has a front element separation problem? (very slight brownish stain on the outer rims inside the front element, that goes away when tilting the lens) Is this going to be a problem, and if so, how big and is it going to get worse? I really wouldn't want to take the lens back without testing, but can't do it because I haven't had a lensboard drilled yet. So anyone know if this is going to affect picture quality at say f/4,5-8 much?

This is stressing me a bit as I really took a dive with this lens, and have plans for it, and now it isn't perfect.

Do I even make sense, as I'm a bit uppset at the moment... Anyway I'm going to ask for a reduction in price, but hope the lens is not completely wasted.

Any info will be appreciated,

Anders

Steven Tribe
10-Mar-2010, 06:35
We all know the feeling!
If this is an older lens with balsam rather than modern glue, then the edging discoloration is just slight discoloration of the balsam rather than separation. This is especialy so if the colour is light and homogeneous rather than "spotty" in appearance. I doubt that you will not notice any further deterioration for a couple of decades at minimum. I sure there are others who will say they have the same edge discolouration with "no obvious effect on imaging qualities".

Anders Korhonen
10-Mar-2010, 06:45
Thanks for the reply,

the lens should be of 1956 vintage (ser.no. 4080057) And it looks more like a slight discoloration and is quite homogenous. So I can start the hassle and mount it and start shooting, and later in life have it fixed, if there still is anybody alive with the skills? :)

Anders

ps. this was the first time I was diagnosed having gottahavenomatter whatthecost, and it was driving me insane for a couple of days =)

Steven Tribe
10-Mar-2010, 06:57
1956 - I don't know whether Voigtländer had switched to synthetics by then. Discolouring might be related to early "trial" synthetic glues. Hopefully someone knows. Reglueing shouldn't be too difficult. I have just looked at the X section of the Heliar and it looks as if you unscrew the front cell, then unscrew the biconcave central lens in its mount, lift out the spacer and the front lens glass will "drop out" through the rear. Even it is was a trial synthetic glue you could replace with the more easily managed balsam reglueing - it is only a doublet.

Sevo
10-Mar-2010, 07:38
1956 is rather past "early" synthetic glues. The big German makers had gone over to a three-component epoxy by WWII, and after the war, UV curing cements (well tested and researched thanks to the gazillion aircraft canopies assembled in the war) already replaced that first cement generation - by the mid fifties, any cement related problems would be due to the introduction of a third or fourth generation rather than an early experiment.

Steven Tribe
10-Mar-2010, 08:34
That would have been my guess too. But the description is exactly like minor balsam yellowing at the edges. Could Voigtländer have continued with the traditional balsam for an older design (It it works - don't change it)?

Ramiro Elena
10-Mar-2010, 08:38
Does it look like this?
http://farm3.static.flickr.com/2794/4371919839_c96533e557.jpg

Mine is S/N 6939717 and so far I couldn't see major problems in my negatives. Stopping it down a little would get the stain out of the way but in my case, I want to use it wide open.

I've come across three cases of this balsam problem with a Heliar lens, one in an old thread in this forum. Is this a common issue with these lenses or pure chance?

Steven Tribe
10-Mar-2010, 09:00
This doesn't look like Canada Balsam failure as "front" edge is very sharp with little discolouration. I would have thought the changes of a sudden complete separation with these hard synthetics is a distinct posibility. The uncoloured Balsam in failing lenses retains a degree of "stickyness" and they "slide" rather than separate. I seem to remember mention of angulon lenses with early synthetic cement actually falling apart in use.

Anders Korhonen
10-Mar-2010, 09:19
Yes it's the same as in the picture, maybe just a little less.

I actually found the photo.net(?) discussion earlier and got worried of the mentioned costs and dangers of repairing it... It's propably going to be ok when shooting, just the "collectability" suffered.. the one thing I used to justify the expense to myself, as I got rid of a pile of 35mm stuff that had lost all value, at a "sufficient" loss in exchange.

Ramiro Elena
10-Mar-2010, 09:28
Bargain a little :)
I got mine for 80 euro so I can't complaint much, maybe you can get some money back?
Like I said, I can't see a major flaw just yet. Maybe in different light conditions such as outdoor shooting. It sucks though because like you say it lowers its value and it could get worse with time.

Frank R
10-Mar-2010, 09:35
Unless you shoot wide open you should not have a problem. Even then you will probably not notice it.

Just shoot with it.