Also, Dagors are really a largeformat lens. All Dagors exibit focus shift, it's due to the left-over spherical aberrations. What this means is twofold: Firstly, you must focus at the working aperture because the focus shifts, the lens' focal length actually gets longer as you stop down. Second, if you want that Dagor look, the "sharp but smooth" with wonderful microcontrast, you need to stop down to about f:11 to f:16. On 35mm, this means the lens will be badly diffraction limited and a real handful to focus.