> I'm intrigued to know how you know ... or at least how you > measured this? > > Vlad Well Vlad, here's how it went down. The lens is marked f3.5 - f16 and indeed the standard apertures are marked on the dial. However, the indicator mark when the lens is wide open reads f4 and when the lens is stopped down the indicator mark travels past f16 to a location that would be approximately f22. I have no idea, nor do I care, if any of the markings are accurate. I just open her up to frame and focus then stop her down about half way. The numbers mean nothing to me and also when the lens is 4" from my subject I can't even see the aperture scale. I can tell you this though, the iris gets bigger and small when I rotate the aperture ring and that's good enough for me. Greg
