Archived posting to the Leica Users Group, 2014/08/03
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I'm unsure about testing with auto ISO on when using increasingly smaller apertures but I notice several things: a) the camera works fine b) the camera seems to ignore gravity c) you have a marvelous collection of books - Ted's among others :-) Nicely done notwithstanding my initial remark. Thanks for sharing this interesting report. Amiti?s Philippe Le 3 ao?t 2014 ? 22:56, Richard Taylor <r.s.taylor at comcast.net> a ?crit : > I recently tested the new full-frame Sony A7s with a 15mm Voightlander > Heliar, 28mm Summicron ASPH, 35mm Summicron ASPH, and a 60?s era 50mm > Summilux and thought you?d be interested in the results. They are shown > in the links below. These are all full-size files and will show the > results most clearly when viewed at 100%. These were all taken at the > closest focusing distance which is the worst case. The corner smearing is > less at typical working distances. The camera has only a 12 MP sensor, > but that is good enough for most of my uses, and the hi-ISO performance, > said to be spectacular, was worth exploring. > > I shot these pictures in RAW and processed them in Lightroom 5.5. The > only adjustments I made were to equalize exposures in some instances and > level those that came out at a small angle. > > I think the Leica lenses worked really well. The smearing in the corners, > even wide open, may not be serious in practice, unless you put your > subject in the corners. The lenses need to be stopped down to at least > f5.6 to reduce the smearing and f8.0 get rid of it completely. > > The A7s is a *really* nice camera. Only a little larger than an OM D > EM-1, it produces good-looking, easy to process files and, as you will see > when you look at these jpgs, the Hi-ISO performance is astonishing. The > EVF is excellent and it?s easy to see the whole frame even with > eyeglasses. With Sony autofocus lenses I think it would probably probably > be a gem. If I were buying one though, I?d probably go for the A7 because > of the higher pixel count even though the hi-ISO noise performance is > poorer. > > But? focusing was a bear. Even at the lowest setting, focus peaking was > sometimes unreliable even wide open. Stopped down, it was almost > impossible to use. I assigned focus magnification to a custom button next > to the shutter release and, with magnification, focus was almost always > spot on wide open or slightly stopped down. Being a disciple of Dr.Ted, > though??Oh, look at that: Wow! click"?that procedure is not for me. A > more deliberate shooter might find it just fine. With wides like the 15, > zone focus worked well. > > I am now of the firm opinion that Leica M lenses are only suitable for > Leica rangefinder bodies. No matter what fancy electronic focusing system > is developed in the future there is no way around the fact that you must > focus wide open to nail focus when viewing through the lens. > > The camera and adapter were rentals and that worked out well. The > Voightlander adapter I used has a cool feature. After releasing a catch, > it?s possible to screw the adapter outward about a quarter inch to allow > close focusing with Leica lenses. I tried it. It works. But, I didn?t > look at any of the images close enough to say anything about the image > quality close in. > > Here are the results. > > 15mm Voightlander Heliar: > http://gallery.leica-users.org/v/rtaylor/PICKS/a7s_leica_lenses/15+Voightlander+Heliar.jpg.html > > 28mm Summicron ASPH: > gallery.leica-users.org/v/rtaylor/PICKS/a7s_leica_lenses/28+Summicron+ASPH.jpg.html > > 35mm Summicron ASPH: > gallery.leica-users.org/v/rtaylor/PICKS/a7s_leica_lenses/35+Summicron+ASPH.jpg.html > > 60?s era 50mm Summilux: > gallery.leica-users.org/v/rtaylor/PICKS/a7s_leica_lenses/50+Summilux+_60_s+era_.jpg.html > > ? and, two shots with the 15 and 28 at a local playground: > gallery.leica-users.org/v/rtaylor/PICKS/a7s_leica_lenses/Playground.jpg.html > > Happy browsing. Comments always welcome. > > Best, > > Dick > > > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information