Archived posting to the Leica Users Group, 1997/03/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 02:59 PM 3/2/97 -0800, you wrote: >A couple of comments regarding M3s and M-lenses: > >I have never seen the use of a wider-aperture lens provide a sharper or better- >corrected image when stopped down than another lens of the same focal length >used >at its full (but smaller) aperture. Thus, it seems that the only reasons to use >say a 90mm f:2 rather than the 90mm f:2.8 or f:4 are: you need the light for the >purpose such as using a finer-grain film, or you want to isolate a smaller >depth- >of-focus. Thus, both the 90mm f:2 Summicron and the 90mm f:2.8 Tele-Elmarit are >sharp at f:2.8; the lesser mass of the later may be a controlling influence >when back-packing, etc. Well, conventional wisdom has it that lenses are better a few, or even one, stop in from wide open--in other words, that the Summicron would be better at f2.8 than the Elmarit, everything else being equal (which it probably never is!).--Charlie Charles E. Love, Jr. CEL14@CORNELL.EDU