I am using a "normal" DSLR as my main camera, but I also play around with a mirrorless, so this issue is only so I can get a better understanding of the influence of focal reducers on lenses. I am using a Sony NEX 5R with a variety of legacy lenses and seem to have ended up with a lot of PK mount glassware. So after reading an article or two and some forums, I got myself a focal reducer to experiment with. It's not a high end product so I wasn't expecting miracles optically, but suffice to say that I am moderately surprised by the performance. Apart from reading and experiencing the "wider" angles and wider apertures which is great for evening photography in the city there is something that I need to get my head around. From the gradations on the lens barrel for focus distances it became aparent that these are now mere numbers and not relevant to anything. Futhermore it is also variable on zoom lenses. There is a point (usually around mid-zoom range) where it is more or less in line with the markings but at the wide and tele end it all over the place. Also the nearest focus point to the camera is much further from the lens than usual. Is this to be expeced or may this just be because the focal reducer I have is an entry level (generic?) unit?