Hello, new member from San Antonio, Texas

[Stephen]

Apr 22, 2015 14:44:11 GMT -5 lonestr said:

Stephen, thank you so much. Now that you have elaborated on the bayonet system, I now have a better understanding of what you are conveying. Luckily I still have the ring attached to the bellow opening. looks like my brother forgot to include it to the compur system when he sold it.

Right, you are very lucky indeed to have the flange, they are the most sought after item from the Bergheil. If the replacement lens fits the thread then another will fit, also it may fit with a sleeve if smaller diameter, but the same focal length of about 105mm.

However, we should remember that only the lens makes the image on any camera, and the Voigtlander Heliar lens was a top quality item, and of good repute. It gave excellent results, that other rivals did not achieve, even the Zeiss Tessar.

It is very sharp at the centre, with a shallow fall off towards the edges, and a claimed luminesance about the image.

The lens was a modified Cooke Triplet, with extra glass elements cemented to the front and rear lenses. This corrected problems with the Cooke at the edges, and allowed a larger relative aperture for the focal lenght.

Tessars rivalled it in performance at medium apertures, but could not rival the maximum aperture of the Heliar.

Stephen.