The 2,8F was made from 1960-1981. During the 70s however, demand for Rollei TLRs declined and fewer cameras were made. Rollei also got into financial troubles during this era. From 1973 on the camera was only available with Xenotar lenses. (According to "The classic Rollei - a definitive guide"). It will be quite difficult to find a camera from the 70s, but this does not matter at all, except for collectors. I would rather buy based on condition than on production year. Rolleis dating from the 60s are perfectly fine, if well cared for.