When did Schneider's quality control improve?

[graywolf]

Actually, the only quality improvement I could find was to reduce the advertised coverage of the lenses in the early 1960's. For instance that famous/infamous 90/6.8 was at one time claimed to cover 100 degrees, and later only 80 degrees. Since there was no change to the lens, that would indicate that people wanted sharper lenses so they made them sharper by disinheriting the un-sharp portion of the image circle.

Lenses that did not need extended coverage were always great. My long gone Rolleiflex 2.8 E2 Xenotar (1957 vintage) was a sharp as one could ask for, but notice that when they went from the f/3.5 to the f/2.8 version of that lens they also went from 75mm to 80mm which indicates that the 75mm would not quite have sharp corners in that format. My opinion was that the Xenotar was a little bit more contrasty than the Planar.

What I am saying here is that I have never seen any quality control issues in Schneider lens if they were in "as new" condition. By "as new" I mean in the mechanical/optical condition they came from the factory in, not cosmetic condition. Remember, a lot of old lenses have been FIXED by IDIOTS.

[Lynn Jones]

The Symmars shown as "convertible" were very low contrast and not very sharp except as converted where they were pretty good. When the Symmars as Symmar S with conventional coating showed up they were truly excellent, and from then on.
Lynn

[E. von Hoegh]

The Symmars shown as "convertible" were very low contrast and not very sharp except as converted where they were pretty good. When the Symmars as Symmar S with conventional coating showed up they were truly excellent, and from then on.
Lynn

The convertible Symmars were and are excellent, sharp, contrasty lenses when used at their prime focal length. They do not of course have as much contrast as the multicoated non-convertible versions, however the difference is not great.

[IanG]

The convertible Symmars were and are excellent, sharp, contrasty lenses when used at their prime focal length. They do not of course have as much contrast as the multicoated non-convertible versions, however the difference is not great.

I think Lynn's statement was the wrong way around, as a whole the lenses are very good, decent contrast etc.

Ian

[E. von Hoegh]

I think Lynn's statement was the wrong way around, as a whole the lenses are very good, decent contrast etc.

Ian

I should hope so. If I have been using a very low contrast and unsharp lens without realising it these past 25 or so years, there is something seriously wrong....

[Ole Tjugen]

Actually, the only quality improvement I could find was to reduce the advertised coverage of the lenses in the early 1960's. For instance that famous/infamous 90/6.8 was at one time claimed to cover 100 degrees, and later only 80 degrees. Since there was no change to the lens, that would indicate that people wanted sharper lenses so they made them sharper by disinheriting the un-sharp portion of the image circle. ...

Except that there IS a slight change in the lens. Pre-1960's Angulons do have a larger image circle, if the purpose is contact prints. The design tweak gave more even sharpness over the advertised coverage, at the cost of a more abrupt loss of sharpness beyond 80°.

I believe most of the "poor" Angulons have been affected by cement creep through improper storage. Since the inner elements in each cell are only held in place by the cement, storing an Angulon "on edge" in high temperatures might cause centralisation to be lost.

[IanG]

I believe most of the "poor" Angulons have been affected by cement creep through improper storage. Since the inner elements in each cell are only held in place by the cement, storing an Angulon "on edge" in high temperatures might cause centralisation to be lost.

Dean Jones (Razzledog) posted on this forum that he'd found that there were significant variations in the cell spacing caused by the Compor shutters (usually too great) and that when he corrected this (by machining the shutter) lenses that had previously been poor performers improved significantly. This would indicate a quality issue with the Compur shutters which was over looked by Schneider.

Ian