|My Retina III S with sharp Xenar 50mm f/2.8|
Retinas were made in Germany by Nagel Camerawerk. Dr. August Nagel founder of Contessa and co-founder of Zeiss Ikon decided to go on his own and started Nagel Camerawerk in 1928. Acquired by Kodak in the early 1930s they made Retinas until 1969.
I love this little lens, it's very sharp and makes great pictures on my NEX-7.
Just like the Steinheil München I posted about earlier I was blown away by the sharpness and lack of chromatic aberration.