Glass Buildings -- NEX-5 & Carl Zeiss Jena Biotar 5.8cm f2.0
I have two working Biotars. This particular one is small with a red T. Not really sure what it signifies, but it's significantly smaller than the other export version which simply says Aus Jena B 58mm f2.0. I like the Aus Jena too. Very sweet bokeh and both are very sharp when stopped down a little. It just boggles my mind that these 30-40 year old lenses still performs so wonderfully today.