Archived posting to the Leica Users Group, 2013/11/19
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]The 102 lpmm were 'discernible' on Micro Ektachrome, which is a very high contrast, super fine grain film. In that regard, digital sensors cannot yet compete nor should they try, as that film was not usable for general pictorial use. The MTF value which resulted in a 'discernible' lp/mm is unknown, of course. The 38 lpmm, which should really be written lp/mm is measured at an MTF of 50%, or 50% contrast which is indeed excellent. On the other hand, you cannot compare resolution figures which were tested by different people at different times using different methodologies. Looking at some Leica MTF charts (Note the above caveat!) the Summilux ASPH also would produce in the region of 40lp/mm at 50% in the center and the edge APS-C figure would be similar, but the edge FF figure is definitely worse. The AA Summicron 50 at f/2 is a lot better, according to Leica's literature. Both of these Leica lenses are significantly better than the 50 DR from the 50's overall. Leica apparently tests lenses, not designs but the parameters are unknown to me. These lenses have to be tested at the same time by the same person using the same methodology (and that includes the sensor). Looks like at the moment the Sony A7R is the only body that qualifies. Henning On 2013-11-19, at 10:22 AM, lrzeitlin at aol.com wrote: >> From LensTip.com > "The Zeiss Otus 1.4/55 compares very favourably with its rivals because at > the maximum relative aperture it reaches 38 lpmm. On stopping down the > situation only improves and by f/4.0 the MTFs are on a record-breaking > level of 50 lpmm. The chart below makes it easier to see that the Otus is > really far better than all its competitors. " > > In October, 1978 the magazine "Modern Photography" in a comprehensive test > of normal lenses achieved a resolution of 102 lpmm with a Leica DR > Summicron 50 mm lens using Micro-Ektachrome film. Other lenses were close > behind. Those made by Nikon, Canon, Minolta, Pentax and Olympus all > reached 100 lpmm. For those who care to look it up, the article was titled > "How Sharp Can you Get?" The experiment was critically evaluated and > appeared sound. Images of the results are presented. > > That was 35 years ago. What am I missing here? > > Larry Z > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > Henning Wulff henningw at archiphoto.com