1) field curvature
There isn't any. My centering test showed sharp corners and the rest of the image wasn't sharp. My explanation for that is that because of the vignetting DOF is deeper in the corners and I wasn't to careful when I focused the corners so while they were reasonably sharp and just in the focal plane the center wasn't.
Vignetting is quite high at 2 stops wide open.
2) sharpness
Now that I am sure in my target: Just wow. I haven't seen something similar before. The Makro Planar 2/100 came close but it had an annoying amount of CA.
3) flare resistance
I performed another test under less demanding conditions and I think that a FE 1.8/55 would have performed better here. If someone could compare them directly that would be great though. I would still call it an average performance. It only becomes an issue if you really push the lens but I like to do that and find it a bit limiting.
I did not want to be contrary, but my initial testing did not reveal any field curvature. Glad to see you addressed that. It is as sharp as any lens I own from corner to corner at large apertures--certainly sharper than the Leica 75/2 and Loxia 50/2 at large apertures and about the same as the Loxia 85/2.4 I think tho with a slightly different drawing style. Do you have the sense that sharpness improves much as it stops down? I think I see some improvement through F4 but F4 and F5.6 seem about the same to me. I do see diffraction at F11affecting the image.
If you have solid evidence which speaks against any of my findings please show it, I do my best to avoid them but as anyone I make mistakes
If I pixelpeep I see small improvements in microcontrast from f/2 to f/2.8 and to f/4 but those are really small. Guess on the a7rii they would be a bit more noticeable.
Luvwine wrote: Phillip Reeve wrote:
Another observation: I compared it to the G 2.8/90 at 1:2.
While the Voigtlander has clearly superior CA control die Sony has a much smoother transition zone. I see no significant difference in sharpness. At f/2 the CV is a tad softer but still very good.
Depth of field is considerably different due to focal length. Remarkable that you find the CA better in the CV as from testing I have seen, the 90 Macro is better corrected for CA at macro distances than the Leica 100 apo and the Zeiss 100 MP. This is indeed a remarkable optic. Thanks for your testing. You are doing an excellent job evaluating the lens with pleasing images. Seems like the lens is great in all areas except flare control, which is average, and bokeh, which is merely very good most of the time. Given that all lenses are compromises, this one has very few (size and weight for its focal length are two more, I guess).
DOF does not depend on focal length (unless object-distance is the same). I just have a tripod and didn't spend much time on the comparison so to refocus I had to move the tripod which results in a different perspective.
I am not at all surprised that the Sony has less CA than the Zeiss but I am a bit surprised, that it outperformed the Leica in this aspect.
I share your conclusion. I will look a bit closer at the bokeh but I need to wait for some lenses to compare it to so that will take some time.
Depth of field formula uses I think focal length, aperture, and distance to subject. In macro testing with a lens that extends when focusing (which changes magnification because of change in distance) being exact is difficult! I was not trying to be critical, just making an observation.
I did not understand it as criticism but since both lenses were set to the same 1:2 magnification and aperture DOF should be more or less the same:
"Generally, when two lenses are compared at the same image magnification and F-number one must discern between two cases. When for both lenses the object distance is much smaller than the hyperfocal distance, the depths of field are essentially the same." http://toothwalker.org/optics/dof.html"]Source[/url] (btw: does anyone know why Toothwalker's site is offline?)
1) field curvature
There isn't any. My centering test showed sharp corners and the rest of the image wasn't sharp. My explanation for that is that because of the vignetting DOF is deeper in the corners and I wasn't to careful when I focused the corners so while they were reasonably sharp and just in the focal plane the center wasn't.
Vignetting is quite high at 2 stops wide open.
2) sharpness
Now that I am sure in my target: Just wow. I haven't seen something similar before. The Makro Planar 2/100 came close but it had an annoying amount of CA.
3) flare resistance
I performed another test under less demanding conditions and I think that a FE 1.8/55 would have performed better here. If someone could compare them directly that would be great though. I would still call it an average performance. It only becomes an issue if you really push the lens but I like to do that and find it a bit limiting.
I did not want to be contrary, but my initial testing did not reveal any field curvature. Glad to see you addressed that. It is as sharp as any lens I own from corner to corner at large apertures--certainly sharper than the Leica 75/2 and Loxia 50/2 at large apertures and about the same as the Loxia 85/2.4 I think tho with a slightly different drawing style. Do you have the sense that sharpness improves much as it stops down? I think I see some improvement through F4 but F4 and F5.6 seem about the same to me. I do see diffraction at F11affecting the image.
If you have solid evidence which speaks against any of my findings please show it, I do my best to avoid them but as anyone I make mistakes
If I pixelpeep I see small improvements in microcontrast from f/2 to f/2.8 and to f/4 but those are really small. Guess on the a7rii they would be a bit more noticeable.
Luvwine wrote: Phillip Reeve wrote:
Another observation: I compared it to the G 2.8/90 at 1:2.
While the Voigtlander has clearly superior CA control die Sony has a much smoother transition zone. I see no significant difference in sharpness. At f/2 the CV is a tad softer but still very good.
Depth of field is considerably different due to focal length. Remarkable that you find the CA better in the CV as from testing I have seen, the 90 Macro is better corrected for CA at macro distances than the Leica 100 apo and the Zeiss 100 MP. This is indeed a remarkable optic. Thanks for your testing. You are doing an excellent job evaluating the lens with pleasing images. Seems like the lens is great in all areas except flare control, which is average, and bokeh, which is merely very good most of the time. Given that all lenses are compromises, this one has very few (size and weight for its focal length are two more, I guess).
DOF does not depend on focal length (unless object-distance is the same). I just have a tripod and didn't spend much time on the comparison so to refocus I had to move the tripod which results in a different perspective.
I am not at all surprised that the Sony has less CA than the Zeiss but I am a bit surprised, that it outperformed the Leica in this aspect.
I share your conclusion. I will look a bit closer at the bokeh but I need to wait for some lenses to compare it to so that will take some time.
Depth of field formula uses I think focal length, aperture, and distance to subject. In macro testing with a lens that extends when focusing (which changes magnification because of change in distance) being exact is difficult! I was not trying to be critical, just making an observation.
I did not understand it as criticism but since both lenses were set to the same 1:2 magnification and aperture DOF should be more or less the same:
"Generally, when two lenses are compared at the same image magnification and F-number one must discern between two cases. When for both lenses the object distance is much smaller than the hyperfocal distance, the depths of field are essentially the same." http://toothwalker.org/optics/dof.html]Source[/url] (btw: does anyone know why Toothwalker's site is offline?)
