I've seen purple color shift on another forum with the 35 Sumi that looks like it could be a little worse than the ZM 35/2 on the Nex-7, but I have no idea about edge resolution.
This is surprising to me because even on my old original NEX5, the Zeiss 35mm Biogon and Biogon C where both just exceptional edge to edge.
I had a 5n for a while too which showed even better corner performance on some wider than 35mm focal lengths, but really surprising if the NEX7 isn't just not as good as the 5n, which we knew, but also step back from the original NEX5, at least in terms of corner performance
On my original NEX5, my Zeiss 25mm had some color shift but was sharp, and was quite good on the NEX5n (though given it was a $1000 lens, had I kept the NEX5n I would probably of gone with the E mount Zeiss 24mm rather than a manual focus RF lenses)
Wonder how poor a lenses like the 25mm M mount would be on the NEX7 ? With the crop factor its just about 35mm so hardly very wide. $1200 camera with a great EVF and controls but no ability to use any RF glass wider than than 35mm equiv ? Even a pretty modest 35mm lens which gives 50mm equiv has some issues ? Yikes
millsart wrote:
Wonder how poor a lenses like the 25mm M mount would be on the NEX7 ? With the crop factor its just about 35mm so hardly very wide. $1200 camera with a great EVF and controls but no ability to use any RF glass wider than than 35mm equiv ? Even a pretty modest 35mm lens which gives 50mm equiv has some issues ? Yikes
You said it. There is NEX7 color shift on the edges of my ZM25 and to a much lesser extent the M35 Summicron ASPH. I'm getting a little more comfortable with these 2 now, but freaked when I saw those red edges. I understand the practice of stopping down to bring those NEX7 edges in, now. I also did a test for field curvature on the ZM25 because the focus peaking makes it so easy. At 5 miles or 5 meters, I don't see any.
I need help here. I tried a Leica Tri-Elmar on my NEX 7 and there is no colour shift, even at 16mm. This confirms another member's experience. That gave me confidence that my forthcoming 24mm Leica Elmar would be trouble-free. But then I also tried a 28mm Summicron, and it shifts. Can anyone explain what is happening, and what this means for the 24mm Elmar?
Here's a comparison of the 24 Elmar, Elmarit, and ZA e. The Elmar seems very sharp in the corners, but does have purple issues. One of the few lenses that seems to avoid blurred corners when purple casts appear:
philber wrote:
I need help here. I tried a Leica Tri-Elmar on my NEX 7 and there is no colour shift, even at 16mm. This confirms another member's experience. That gave me confidence that my forthcoming 24mm Leica Elmar would be trouble-free. But then I also tried a 28mm Summicron, and it shifts. Can anyone explain what is happening, and what this means for the 24mm Elmar?
the design of the lens plays a much bigger role in whether it color shifts than the actual focal length. one lens being 16mm and the other 28mm doesn't indicate which will shift more as the 16mm could be a much more retrofocal design than the 28mm. the easiest indicators to look for are how close to the sensor the lens diaphragm and rear element are (the closer they are to the sensor the more likely you are to see shift), but even that does not tell the whole story as some lenses (like the new fujis) could have a rear element designed specifically to straighten out rays before they hit the sensor. the only way to know for sure is to test the lens out or do some ray tracing if you can get an accurate lens diagram that includes refractive indexes etc.
Hi. The issues with the ZA 85 are apparently from f1.4 to f2.8-ish, and it's kinda tough to tell with your f1.4 shots, with the exposure differences. It'd be cool to see more, and maybe at both native rez and resized to the same size. Thanks!
Yeah, Rob got some amount of grief over that test series didn't he? Thinking back to the fall of last year it seems like he was the first to provide a useful heads up with respect to RF lenses on the NEX-7 and some of the issues we'd later all be talking about.
For my part I was hoping against hope that Rob had a bad body sample or that some magic Sony pixie dust would be sprinkled on shipping cameras that also had to miraculously avoid being trapped under nine feet of floodwater. Probably I'm not the only one who held out hope longer than a rational mind ought to have.
Despite the A mount lens on NEX-7 tempest brewing, SLR lenses on NEX-7 do seem to inhabit the sweet spot. Rob included a Zeiss ZF.2 Nikon mount 35mm f/1.4 at various apertures on NEX-7 in that same series and it certainly looked a heck of a lot better. Here it is at f/4:
michaelwatkins wrote:
Yeah, Rob got some amount of grief over that test series didn't he? Thinking back to the fall of last year it seems like he was the first to provide a useful heads up with respect to RF lenses on the NEX-7 and some of the issues we'd later all be talking about.
i still think his tests are worthless for anything other than determining color shift since some (possibly all) of his rangefinder lens shots are clearly missfocused. look at the 85mm shots for obvious examples. i think he just turned each lens to infinity or something...
