Emil von Hoegh, designer of the Dagor lens, was born May 10,1865, 150 years ago tomorrow. See: http://skeel.info/getperson.php?personID=I29001&tree=ks
Among the other lenses he designed were the Hypergon and the Celor. Zeiss continued production of the Dagor and the Hypergon after acquiring the C.P. Goerz company in the 1920's. And of course the Dagor was manufactured in the U.S. by the C.P. Goerz American Optical Co./ Goerz Optical Co.

As you can see from the link cited, the centennial of von Hoegh's death was this past January.

If you have a Dagor, use it tomorrow in commemoration of Emil's birthday! I intend to.
David