These old East German lenses are cheap (some exceptions) and optically fantastic. My favourites are the Carl Zeiss Jena 80mm F1.8, the Carl Zeiss Jena 200mm F2.8, which are harder to find than most other focal lengths. In general, all of them are optically good, but the material used and built quality is no where close to the old japanese lenses.

On the photo, the big gun on the top left is the Carl Zeiss Jena Sonna 200mm F2.8, the two next to it, are the Pentacon 135mm F2.8 Electric and non Electric versions. Second row from the top on the left is the Carl Zeiss Jena Pancolar 80mm F1.8; the five that follow are various 50mm F1.8 Pentacon and Meyer Optics, etc. Second last one on the third row is the Pentacon 29mm F2.8, and the one on a row by itself is the Pre-set type Pentacon 30mm F3.5.

Still looking for the 300mm, 35mm, 20mm, 24mm.