This lens a big gun, I only owned it for a couple of weeks before I sold it. Why? Because its heavy, 3.3 kg means impossible to use in hand. Sample pictures are all taken by hand except one. If you are ready to use a massive tripod all the time, its probably a good choice, but optical quality is far from that of other East German lenses. I changed to a 500 mm Russian mirror lens, mirror lens is small, easy to carry and very sharp. Ok, bokeh is ugly but if your target fills the entire screen , bokeh doesn’t appear at all. So my conclusion, for a cheap budget I recommend you buy a mirror lens rather than old big glasses like any Pentacon, Praktica etc above 300 mm