Quote Originally Posted by arri View Post
Today I wanted to compare two lenses.
1. the Wollensak Verito 8 3/4" f/4.0 but the rear cell with 14" only
2. the Voigtlander W.Z. 360mm f/9.0

Both lenses have an identic focus length, the rear cell of the Verito is a cemented two element lens and the Voigtlander W.Z. is a two element dialyt system with two different foci.

Sorry, but I made a mistake, I forgot to calculate the correct aperture value of the Verito cell. I used the aperture scale of the complete lens and set it to f/8 but with the rear cell alone it is ~f/10.
The W.Z. were used with open aperture f/9
Wonderful imagery.
I measured my Verito 8 3/4" with the aperture set at f8 and the front cell off and the aperture measures 21mm, which would come in at f17.
f10 at 355.6mm (14") would be 35.56mm aperture diameter. That works out to about f4+1/2 on the dial. If I am right ( and my math skills are declining) then your comparison was f17 vs f9, which goes a way to explain the sharpness of the Verito image.