FWIW I received mine today and, being a pixel peeper, did a number of brick wall tests (at enough of a distance and with enough adjustments and repetition to make an initial conclusion) as well as shooting up to an angle to a slanted target (a roof) to see what was happening on the Z-axis. I used the A7R VI on a tripod and remote shutter, electronic shutter, and when there was wind increased my shutter speed to around 1/500s as needed. I found a few things:
-When shooting the brick wall, the lens was sharp wide open across the frame at 200-400mm. Stopping down to f/6.3 made a very small improvement in the center and midframe, but the corners were actually better in some cases at the maximum aperture. Basically, it was fully sharp wide open.
-At 100mm, the corners were softer but also on my copy the left edge was soft and didn't become convincingly sharp until f/10. The right side was better, but overall I could see that peak resolution was better from 200-400mm across the frame. If the decided to optimize for the long end then that would seem to be a good design choice, at least for my uses.
-I shot the slanted target, the roof, and found that sharp detail ran along the red line as shown below (this example at 200mm):
This tilt in the plane of focus seems to be present across 100-400mm, but it is more pronounced at 100mm and eases at 400mm, but it is still there to some degree. I think for those shooting sports or birds or those who shoot where having a flat plane is not critical, you will be happy, because even the flat target looked good. I am not sure yet because I want to also shoot landscape and I haven't determined if this is acceptable for my uses. I have other Sony telephoto zooms including the 50-150 and 70-200 II and they don't have this behavior, so I am wondering if another copy might do better.
FWIW I received mine today and, being a pixel peeper, did a number of brick wall tests (at enough of a distance and with enough adjustments and repetition to make an initial conclusion) as well as shooting up to an angle to a slanted target (a roof) to see what was happening on the Z-axis. I used the A7R VI on a tripod and remote shutter, electronic shutter, and when there was wind increased my shutter speed to around 1/500s as needed. I found a few things:
-When shooting the brick wall, the lens was sharp across the frame at 200-400mm. Stopping down to f/6.3 made a very small improvement in the center and midframe, but the corners were actually better in some cases at the maximum aperture. Basically, it was fully sharp wide open.
-At 100mm, the corners were softer but also on my copy the left edge was soft and didn't become convincingly sharp until f/10. The right side was better, but overall I could see that peak resolution was better from 200-400mm across the frame. If the decided to optimize for the long end then that would seem to be a good design choice, at least for my uses.
-I shot the slanted target, the roof, and found that sharp detail ran along the red line as shown below (this example at 200mm):
This tilt in the plane of focus seems to be present across 100-400mm, but it is more pronounced at 100mm and eases at 400mm, but it is still there to some degree. I think for those shooting sports or birds or those who shoot where having a flat plane is not critical, you will be happy, because even the flat target looked good. I am not sure yet because I want to also shoot landscape and I haven't determined if this is acceptable for my uses. I have other Sony telephoto zooms including the 50-150 and 70-200 II and they don't have this behavior, so I am wondering if another copy might do better.
Jun 13, 2026 at 09:03 PM
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