Archived posting to the Leica Users Group, 2004/11/03
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Dan, Sorry, twelve-hour day in the office today and am just getting to my mail... "Bokeh" is one thing, "brittleness" is another. I'm not saying that APO correction generally means that some images in harsh side-light will be brittle. I'm observing that LEICA lenses in the 90mm - 100mm range appear to have this tendency, whatever their reasons may be, the 90 APO ASPH in particular. Since 2000, the direction Leica has been going in lens design as exhibited by the 28 ASPH is a GOOD THING in my view. The results aren't harsh and the corrections produce images in contrasty light which would have been almost impossible a few years prior. As I said earlier, I have ordered a 50 ASPH in the hope that this trend in lens design continues. I'm just suspicious of the APO correction Leica did in the past and won't buy a lens on blind faith with this designation until I've seen many examples of its output. Trust this clarifies... William At 08:06 AM 11/03/2004 -0500, you wrote: >I've missed something here. I can understand why someone might not like >the ASPH correction in a lens; I *think* it is residual spherical >aberation which is the basis for lovely "bokeh" which people get soft and >fuzzy over (or conversely might be the cause of "brittleness"), and which >is highly corrected in aspherical designs. APO design merely reduces >chromatic aberation, which I can't see having an unintended detrimental >effect on a len's performance. > >-dan c. > > At 07:48 AM 03-11-04 -0500, William G. Lamb, III wrote: > > >[snip] > > > >So let's not get too wound up here, O.K.? I would LOVE to fill that 75mm > >frame on two of my M's. If it's an ASPH, that could be very good. If it's > >got APO correction, I'll be more inclined to wait and see some results > >before springing for one. That's all...