I just got a Domiplan yesterday - I was curious to sample East German optic but it seems I picked the wrong lens model to start with. My copy is in very good mechanical condition and the glass is clear, but the IQ wide open is just horrible. Stopping down the lens seems to produce small progress towards acceptable IQ, but I've never seen a lens so bad. Is this the way this lens was meant to behave optically? Or am I missing some tiny adjustment? The rear element can be removed easily as it is only kept in place by those three screws - I'm wondering if it got misaligned, or if tinkering with it may make the results better. I tried a bit, but I don't see much improvement and I don't think there are really too many ways of mounting it. I'll probably try placing it in reverse position, just for fun, to see if things can get even worse optically.