Archived posting to the Leica Users Group, 2001/08/21
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 8:06 PM -0700 8/21/01, James Morehouse wrote: >I've used both the Leica and OM systems for over 20 years. The >results here don't contradict my personal experience. > >Jim Morehouse <snip> >>Strange results, and testing, to say the least! >> >>-- While I have used some Olympus equipment (most Pen lenses and some OM), and I always found them to be generally competitive with Pentax, Minolta, Canon and Nikon, I never found them to stand above those other makes, nor a number of older Leitz products. I haven't used any Olympus products for 15 years so I will not comment further. To things I have used and have extensive knowledge of: 1. The Micro Nikkor 55mm/2.8 AIS scores significantly higher than the 90 A-A. This is a huge surprise to me, and I'm sure to most others that have used these two lenses. 2. The Minolta MC 58/1.2 Rokkor scores about the same as the 90 A-A. Again; far from my experience. 3. The 28-85 3.5-4.5 Nikkor at 85mm is essentially the same quality as the 90 A-A! Hah! Methodology: 4. The tester gets significantly different results from mirror up and diapghragm pre-fire. This means that the support is not all that strong. If he is using the same support for his 'best' results the assumption has to be that with further stability he could get even better results. If I test lenses for my own purposes the support is going to be steady/solid enough that the mirror, diaphragm, shutter and trucks going by aren't going to make any difference. A whole different order of support is going to be used. Otherwise I am testing on the support, shutter, diaphragm mechanism, etc. and lens as part of a system test, and I cannot/will not make conclusions about the lens on that test. Have a look at the test of the 250/2 Zuiko. The excuse that this is a heavy lens and therefore hard to get steady is absolutely no excuse. You just bolt it to some concrete if you really mean to test the _lens_. 5. He views the film projected on a screen/surface with a (Rollei?) projector fitted with a zoom projection lens. Not exactly state of the art in analysis. Fujichrome 64T is a decent enough film, but not the best either. The net result of the methodology lapses noted (there may be others, as he doesn't go into that much detail) means that most lenses will be brought to a fairly low common denominator, which you can see if you look at a number of the results. Except for a few deviations, most lenses that you would expect to be useable end up with up with one or three A's at the edges and a couple at the middle. The only lenses that get significantly better results are some Zuikos. That makes me a bit suspicious as well. Some are definitely excellent lenses, but considering the results he achieved for an extremely good non-Zuiko lens, the 90 A-A, the relative standings are suspicious. Also note that many Zuikos got a top mark, or at least an A- at f/22. If you only deal with what is theoretically possible, saying that no lens achieved a better value at any aperture than what the best lens achieved at f/22 means the bar was set too low. I don't think these tests can be taken very seriously, even if you are very satisfied with your Olympus lenses. I'm very happy with many of my non-Leica lenses (which outnumber my Leica lenses by a wide margin), but I try to be objective about what they can do for me. I think all you can say that these are the results he obtained using his methodology. Take it or leave it. - -- * Henning J. Wulff /|\ Wulff Photography & Design /###\ mailto:henningw@archiphoto.com |[ ]| http://www.archiphoto.com