Archived posting to the Leica Users Group, 1997/12/08
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Erwin Puts, First & foremost, thanks for posting a highly exegetic MSG; it got me to thinking about the 280 f4 again. Knowing that Leica themselves has classified the 280 f4 as a "diffraction limited lens", & taking into account your MSG; I went to the BAS charts looking for supporting data. Sure enough, f8 resolution is ever so slightly lower than f4 resolution; & conversely f8 contrast is ever so slightly higher than f4 contrast. Although the differences are slight, it's a pattern that fits your theories; & L0 & behold, the same pattern applies to the 180 f2. However, the 180 f3.4 is incredible; both the sharpness & contrast increase from f3.4 to f8. Therefore, either the 180 APO Telyt is not a "diffraction limited lens" or the BAS testing is not comprehensive enough. However, maybe it's meaningless to discuss a lens which is so good that it defies all attempts at categorization :~)! If you care to comment; it would be appreciated! In any case these are truly wondrous "dream" lenses. Any one fortunate enough to own them understands what's meant by a "dream" lens ;~)! Tom D.