I have one too and think its a great lens, mine is sharp right through and works out about 24mm on Pentax Dslr, there is some distortion, but it can be removed with a program called Rect Fish. Like all Russian/Soviet/Ukrainian lenses quality control is the problem so you can get a good one like mine or a total lemon. But it is useful as a quality wide angle, and I have used mine far more than I would have thought, I suppose if you get the chance to try one first then have a go you might find it a good piece of equipment

Thanks all! thought I was ok with the Samsung afaik its a K10D anyway, glad to be aboard

Hello to all here, been a member for a while not posted anything as yet some may know me from mflenses or the yashica forum, hope to learn a lot and hope my Samsung GX10 is not held against me, did have a K100d but its been passed on to a friend.