From top to bottom are at F/2, F/2.8, F/4, F/5.6, F/8, F/11, F/16, F/22.
Left 2 columns are sagittal and tangential at frame center.
Middle 2 columns are sagittal and tangential at 1/2 of frame.
Right 2 columns are sagittal and tangential at frame border.
The number 36 means there are 3600 lines across the vertical of frame(each step is 300 lines).
Regarding the detail of the test procedure please reference to "鏡頭測試項目解說".
Comment:
The corner resolution seems very bad at large aperture. It doesn't improve much until aperture shrink to F/8. Some reports said this is because the astigmatism of wide angle lens. But we think this is only because the misalignment of the optic elements. This the evidence(hit for 1600 pixel picture):
We try to analysis the aberration of 4 corners at F/2. As you can see the worst is at the down left, the best is at the up right. Due to the lens's element is an ideal circle, so the performance at the same radiant must be the same. So we do think this corner aberration is come from the misalignment of elements in production. The Voigtlander lenses come from the Ultron series are not as good as Super Wide-Heliar 15mm or 12mm. If you have any further question welcome to discusses.
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