Marc wrote: "First, Zeiss recomputed the entire Tessar range in the late 1950's. This was primarily done for use on the Contaflex SLR's -- the recomputed Tessars appear on the Super B, Super BC, and S -- but the improved design was extended to the Rolleiflex T. As the recomputed lens appeared in 1962 and the T in 1958, I would suggest that early T's had non-recomputed lenses." The Rolleiflex T was touted as having a recomputed Tessar from its Photokina introduction; likewise, early sales literature for the T mention the new design, featuring a 'rare-earth element', presumably referring to the lanthanum glass. Regards. Matt