Archived posting to the Leica Users Group, 2014/02/21
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]This was a totally unscientific test, but Jim Laurel asked a question, and I had the stuff to answer it, and I think it will help me in the future. The question was, Does the V/C 15mm exhibit magenta corners with the Sony A7r? Also up was the question of smearing with wides on that camera. Looks like the answer is yes on both counts, though it may not be only the camera. (I haven't tested the lens for smearing on my M9.) I also held a ir-uv cut filter up to one side of the lens, and to my eye, it seemed to lessen the magenta effect. If I can find one of the correct diameter, I'll try that one again full frame. I also did the same shot with my 21 pre asph Elmarit and the Sony Zoom set at 28mm. I just set the camera at auto for all 3 lenses. This test probably is not in depth enough for some of you, but it tells me what I want to know, and that's to use these two lenses on my M9. Easy enough, as I barely use them anyhow. I rarely take a 35 off my camera ever except for my flower shooting. Here are the snaps. http://sonc.com/look/?page_id=3324 To see full sized jpegs of the four shots, go to www.sonc.com/a7r www.sonc.com/a7r/15-big-DSC00641.jpg www.sonc.com/a7r/21bigDSC00648.jpg www.sonc.com/a7r/28zoomDSC00650.jpg www.sonc.com/a7r/filter-bigDSC00645.jpg On Fri, Feb 21, 2014 at 6:23 PM, Geoff Hopkinson <hopsternew at gmail.com>wrote: > Leica raah raah forum !! > On Feb 22, 2014 1:00 AM, "Steve Barbour" <steve.barbour at gmail.com> > wrote: > > > > > On Feb 20, 2014, at 5:46 PM, Jim Laurel (gmail) <jplaurel at gmail.com> > > wrote: > > > > > All I've seen, Steve, is some anecdotal evidence. Don't get me started > > on Ken Rockwell, but on this page, he does have some examples of a 21mm > > Super Elmar-M adapted to the A7 that appears to show sensor reflections > and > > smeared corner detail. Lurking around the dpreview forums, I've seen > others > > report similar results. But of course it's hard to know for sure > > > > > > http://www.kenrockwell.com/tech/comparisons/2013-12-leica-sony-canon/ > > > > hi Jim, we are happy to see you back. My point of course is....we don't > > exactly have PROOF of anything, though we do have anecdotal and selected > > stories by people with an agenda. No completeness or worst case scenarios > > by unbiased individuals with data for the leica M240, as well as the Sony > > A7 and A7r. Selected stories to make a point by people who wish to make > a > > point. No semblance of a real unbiased careful comparison. All of this is > > then presented to a leica rah rah forum by people who like leica, whether > > they use one or not.. I would like to know what the real facts are, based > > on real world data, with carefully done comparisons. And if the cameras > in > > question have flaws in some areas, I will use the cameras accordingly, > > always the case for all of us. > > I used a CV 12 mm lens on my A7r, with many usable results, but some > > unacceptable results as well. > > That alerted me to be careful, especially with the widest of the wide. > > Extrapolating this to all lenses under 50mm is not a conclusion based on > > the facts. Some results of the widest lenses are acceptable, and we need > to > > have some reasonable ground rules. It occurred to me that we don't have > > rigorous comparative data, even for the M240. What is clear is that > many!! > > lenses on the A7r, give incredibly wonderful results, it would seem far > > greater in number for the A7r than the M240 because the list includes > most > > lenses ever made by most optical companies, including all of the leica R > > lenses. > > > > Looked at in this light, I feel that the least we need to do, is approach > > this question with complete understanding of the situation, an open > mind, > > and armed with some real world comparative data. > > > > By the way, the above subject line says OT, but in my estimation this > > subject is very much on topic. > > > > thanks for bringing it up, > > > > Steve > > > > > > > > > --Jim > > > > > > > > > > > > On Feb 20, 2014, at 5:10 PM, Steve Barbour <steve.barbour at gmail.com> > > wrote: > > > > > >> > > >> > > >> Sent from my iPhone > > >> Steve Barbour > > >> > > >> On Feb 20, 2014, at 4:39 PM, Jim Gmail <jplaurel at gmail.com> wrote: > > >> > > >> Aren't there a lot if reported issues with adapted lenses? The Leica M > > primes, at least, seem to perform much better on the M240 than on the A7. > > >> > > >> where is this proven? > > >> > > > > > > > > > _______________________________________________ > > > Leica Users Group. > > > See http://leica-users.org/mailman/listinfo/lug for more information > > > > > > _______________________________________________ > > Leica Users Group. > > See http://leica-users.org/mailman/listinfo/lug for more information > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > -- Regards, Sonny http://sonc.com/look/ Natchitoches, Louisiana 1714 Oldest Permanent Settlement in the Louisiana Purchase USA