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View Full Version : Schneider - Kreuznach Angulon 165/Compur Shutter #2 problem



William Snodgrass
3-Apr-2004, 01:37
Hello, I recently acquired a Schneider - Kreuznach Angulon f:6,8 F=16,5 cm lens mounted in a Compur Shutter (appears to be the #2, has 4 blades). On slow speeds the shutter would sometimes stick so I removed the rear element and found that the front element is ever so slightly blocking the four blades of the shutter. The blades have chipped off the black paint on the front element in four places where they catch. After removing the front element the shutters work fine. It would seem that what I should do is add a very small shim, (less then half a millimeter I guess) to the front shim to keep it from catching the shutter blades. Consequently there would be no way to increase the rear element to match. So I'm wondering how "bad" would be the effect of shimming the front element slightly away from the rear element? Further, does anyone have any more information on this lens and should it perhaps be mounted in a different shutter? I was able to get some information from Schneider Optics web site about the lens: http://www.schneideroptics.com/info/vintage_lens_data/large_format_lenses/angulon/data/6,8-165mm.html Thank you for any help, Bill Snodgrass

Michael S. Briggs
3-Apr-2004, 01:44
If the cells are currently correctly spaced, changing the spacing by 0.5 mm is likely to adversely effect the performance. Does it look like the cells were factory installed in the shutter, or is it a later effort by someone? Do the aperture scales look like a factory made item?

The best indication of the shutter size is the maximum diameter of the aperture.

I suggest sending the shutter and lens to an experienced repair person.

William Snodgrass
3-Apr-2004, 13:24
Hi Michael, Thanks for the reply. I'm sorry if I'm being dense but I don't quite understand your questions. I'm assuming by cells you are referring to the metal/aluminum threads that are on the front and back of the shutter. Although they look shinier then the rest of the Compur they also look to be the original pieces of the shutter. So I think they were factory installed. The aperture scale has the f-stop scale on the side of the Compur that has readings from 6.8 to 32. This scale does look to be the original scale. The iris control for the aperture is a ring on the back of the Compur that will open the iris or aperture all the way. The maximum hole size is 35 mm. Thanks again for your reply. I probably will have to take it in I just reluctant to spend more money if I have to. :> Bill Snodgrass

Kerry L. Thalmann
3-Apr-2004, 22:29
Bill,

The fact that the focal length is engraved in centimeters (rather than millimeters) indicates a very old, Pre-WWII Schneider lens. You can determine the approximate date of manufacture at:

http://www.schneideroptics.com/info/age_of_lenses/

I'm guessing it's probably from the 1930s. If it is indeed that old, the original shutter was possibly a dial set (shutter speeds are set by turning a little wheel at the top of the shuter) Compur (if indeed it originally came in a shutter). If your lens is in the newer style rim set (shutter speeds are set by turning a knurled ring that encircles the entire circumference of the shutter body) Compur shutter, it was possibly remounted (perhaps carelessly) at some point. It is unlikely that it left the factory in such inoperable condition (although Schneider's Pre-WWII quality control was not the greatest).

If my descriptions of dial set and rim set Compur shutters were too confusing, check the photo at:

http://www.skgrimes.com/compur/compurbg/c3.jpg

The top left shutter in that photo is a dial set Compur. The top right is a rim set Compur.

It really sounds to me like your lens cells (a lens cell is the subassembly consisting of the metal barrel and glass elements that screw into the front and rear of the shutter - your Angulon lens has four elements, but only two cells - one front and one rear) were remounted in the current shutter by someone who didn't know what they were doing. They probably just found a shutter with the right thread size and screwed the cells in place without regard for proper spacing. Dagors (and the Angulon is a derivative of the Dagor) are sensitive to proper cell spacing. If the lens was mounted improperly the performance could suffer - even if you can get the shutter working.

The best course of action would be to send it to a qualified repair shop for an estimate. Given that Pre-WWII Angulons were not coated, and quality control wasn't the best (have you tried shooting with the lens - how is the performance?), it may not be worth the cost of fixing (depends on what's really wrong and how much it will cost to make it right). If the estimate is more than a couple hundred dollars, you may be better served by trying to find another used Angulon properly mounted in a working shutter. Look for a Post-WWII coated sample in a rim set Compur shutter - engraved in millimeters. Kerry

William Snodgrass
4-Apr-2004, 02:50
Hello Kerry,
Thanks for your reply.

The lens, according to the Age of lenses page at Schneider Optics, places the lens at about the middle of 1938 (No 1343904). There are two lens cells (or Groups) front and rear with six Lens Elements, three elements per group (see also Schneider Optics for Angulon 6.8/165mm http://www.schneideroptics.com/info/vintage_lens_data/large_format_lenses/angulon/data/6,8-165mm.html).

The Compur shutter information that I have gleaned is that it is a #2 Compur (726371), also known as a Dial set Compur, made in Germany. The shutter speed dial has fancy "FD" letters on the dial plate which seems to allude to a Mr. Friedrich Deckel. The speeds of the shutter are from 1 to about 250. The shutter control is most interesting in that there are six sets of letters, three opposite the other three. There is a marker on both sides for each corresponding letter. My assumption here is that it is for German and English settings. So with the control set to "Z" or "T" that would be Z=Zeitaufname (Time & Motion Study) or more likely Zeit (Time) and T=Time. With the control set to "M" or "I" M=Momentaufname (Moment in time or snapshot) and I=Instantaneous and the last control setting would be "D" or "B" B=Bulb but I do not know what "D" is equal to. I have tried the different German translations for bulb (Beliebig, Birne) but no "D" appears. I don't know German so if anyone knows the answer to this I would be much obliged. Other trivia is that Friedrich Deckel developed the first mechanical central shutter called the "Compound" shutter and later created the Compur, a combination of the words Compound and "Uhr", German for clock. The first Compurs were made in 1911 but I have know idea when this was made but it seems pretty early.

After looking at all of this again and again I feel like that the lens was probably meant to go in this shutter but that the lens threads are somehow a little off. I can't seem to understand how the lens threads go into the shutter without exploring more with the shutter and do feel that the suggestions so far to take it to a professional is warranted. I have made a few shots with it but I am so new to large format photography that I could not say whether the lens was poor or not (my very first pictures I had the film in backwards!). For the few pictures that I have taken the pictures seem relatively clear and in focus. However there tends to be less resolution closer to the edges of the print but in all fairness I have to say that I am using this lens with an 8x10 camera so I understand that this is a pretty wide lens for 8x10.

Thanks again for the response Kerry. I will see what it would cost to have this looked at and if it is too much then I may leave it and not worry about it. I would not at this point be shooting very dark pictures and can probably live with the fact that it sticks at slow speeds (just messes with my mind because now I know why :>).
Bill Snodgrass

Řyvind Dahle
4-Apr-2004, 10:21
Compare the resolution on different pictures as you screw one cell away from the shutter, and see if you can find a new, better position. You can then make your own shims out of brass

Řyvind:D

Michael S. Briggs
4-Apr-2004, 12:26
William, from your description of the shutter, you have a dial-set Compur. It should look like the one on the uppper-left on the link Kerry gave, http://www.skgrimes.com/compur/compurbg/c3.jpg.
I have never used a dial-set Compur, but they have a poor reputation for lasting. If the repair estimate is high, you might want to forgoe the repair and apply the money towards another lens. A post-WWII lens would be at least single-coated and most would be in more reliable shutters. 165 mm is very wide for 8x10. The modern lenses of about this focal length that will cover 8x10 are expensive. There are many past threads discussing wide-angles for 8x10.





The "Z" is for "Zeit&quot. The controls of the dial-set Compur are similar to the Compound. Unlike the dial-set Compur, the older Compound is considered reliable.

Ole Tjugen
6-Apr-2004, 08:19
Your Angulon doesn't have to be bad just because it's old - I use even older lenses regularly.

Unlike some others, I have had no problems whatever with the dial-set Compurs.

The problems you describe certainly seem like someone has mounted the lens wrong in the shutter - if the glass looks good, it would cetrainly be worth having it checked out. They don't make them that small any longer!

William Snodgrass
8-Apr-2004, 22:32
Thank you for all of the replies. At this point I think I will have to do with the front lens element catching the shutter blades. I may take it in but I need to purchase a longer lens anyway, although I do like how wide this lens is.

If anyone knows what the "D" on the shutter control stands for that would be great (see my previous post above).

Thanks again, Bill Snodgrass

Ole Tjugen
9-Apr-2004, 06:21
That one slipped my mind...

Z - "Zeit" M - "Moment" D - "Dauer"

William Snodgrass
9-Apr-2004, 20:56
Thanks Ole Tjugen!
Bill