Archived posting to the Leica Users Group, 2020/05/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Report back tomorrow. An excellent idea. On Mon, May 25, 2020 at 3:24 PM Aram Langhans via LUG <lug at leica-users.org> wrote: > Any thoughts as to the color shift maybe due to IR like the M8? Maybe the > new cover plate is not as efficient at filtering IR as the original. Have > one of the IR cut-off filters from M8 days to check? > > Aram > > -----Original Message----- > From: Frank Filippone > Sent: Monday, May 25, 2020 1:18 PM > To: Leica-Users-Group > Subject: [Leica] More Nerdy stuff.... Sony A7 with Leica lenses. > > If you own or have contemplated the purchase of a Sony A7 series body to > use with your Leica M lenses, you have heard that Leica WA lenses show > smeared corners due to the closeness of the lens to the sensor.. the > image ray's angle causes problems. > > A company, KolariVision, has a modification to the A7 series that > replaces the standard cover plate ( the one that fell OFF my M9) with a > very thin glass cover plate ( I think it is 0.2mm thick. the Leica OEM > plate is approx 2mm thick). This improves the image quality in the > corners of the frame.... So the question is, if I read all the > literature, is any or all of it true? Is it just marketing BS? > > I went testing ( yes, again). > > One of the most awful lenses for this problem used on the Sony A7 bodies > that Leica has made is the 28 Summicron ASPH. V1. > > One of the best lenses on the Sony bodies is the WATE... 16/18/21mm F4 > Wide Angle TriElmar I tried both. I also tested a 21mm SEM, because I > was asked to. > > The cameras were setup identically. The only thing that changed in this > test was the body.( Tripod, same shutter speed, same apertures, same > lens.... ) > > ::::SPOILER ALERT:::::: > > The Kolari modified body FAR exceeded the IQ of the unmodified body in > the corners... > > A7rii vs A7rii Kolari > > With 21mm SEM and 28mm Summicron ( notoriously bad on Sony bodies) > > At ISO50 > > At Fwide open, F4 and F8 > > Distance from camera to center of image was about 15 feet. Tripod of > course. > > The camera body was place at an angle, allowing for easy access to the > corners ( the horizon line was set corner to corner) ...... Essentially > stressing the lens corner quality as much as possible..... > > Focusing was done by x10 focus enlargement in MF mode in the center of > the image...... I did not focus in the corners.... I use a ground glass > kind of focusing, no high tech stuff. When it LOOKS sharp it IS sharp. > > Focus was not done at each F stop... it was done wide open only. Care > was taken to not move the focus ring when changing aperture. > > In the center of the frame, there was little to no difference in the > images. The cameras produced very similar images.... see comment below > about the color shift..... > > There was NO condition where the Kolari modified body did not beat, by a > large amount, the corner sharpness of unmodified A7rii. NONE. 21 SEM, > WATE, 28 Summicron V1.... All the same result. > > I also added on the M240/28mm Summicron as a test vehicle against the > Sony body.... The Kolari body BESTED the Leica body. Not by as much as > the Kolari bested the unmodified body, but it was pretty obvious. > > There is no question in my mind, that the Kolari Modified thin glass > cover plate was a BIG improvement to the lenses tested, and I am willing > to bet, it is a big improvement to ALL WA lenses...... > > Further note: There is a color difference between the Kolari body and > the Leica or Sony unmodified bodies. The color shift is expressed as a > purple tint in the Kolari modified body. Especially in the gray areas.... > > I should have shot a white card and color corrected on that..... maybe > another day..... > > I am pretty anal when I do these tests. I am careful, I look at the > images 1:1 in comparison mode in LR. The results are correct. > > If you want to up your Leica IQ game in the corners.... send a Sony A7 > family body and $400 to Kolarivision, and get it done. It is cheaper > than buying a M-60MP body will be..... > > I did not test native lenses on the modified body. Maybe another day...... > > Paul Roark ( who found this out for himself several years ago and got me > thinking down this path) ... want to add anything? > > > PS: If you type in only Kolari to your Google search, I think you get a > porn site.... You will figure that out pretty easily. It needs to be > www.KolariVision.com > > -- > Frank Filippone BMWRed735i at gmail.com > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > -- Frank Filippone BMWRed735i at gmail.com