I have several old m42 mount lenses which have been hiding in my closet that I am trying out with my new EOS 77d. I am a novice but I thought it would be fun to show some of the results here. I dont know what to expect with the others but I was pleasantly surprised with this one. The first two were 230mm at f22 and f5.6. The next two were at 90mm at f22 and f4.5. I like the difference in the depth of field in all of them but what I like most is the quality. I didn't know what to expect from this lens but I didn't expect this much. Let me know your thoughts.