Reader Comment: Sony FE 12-24mm f/4 G Right Side Blur
Kai O writes:
I’m a subscriber of your site and I noted that you had a “right side blurry” FE 12-24mm lens in your review.
I just bought one and see the exact same issue with my example. The 12-24 at all focal lengths has right side (top, edge and bottom) all blurry starting from approx right ¼ to 1/5 of the frame, otherwise left hand side and middle are stellar.
I wonder if you have received a replacement? Is this a wide spread issue? For me I’ll have to drive an hour to the city to return it and hope they got another copy available. I’m very disappointed with their QA.
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I tested it against Voigtlander 12mm E mount, 15mm M mount, Loxia 21, Zeiss 2.8/21 ZF.2, Nikon 14-24 all on the same a7r2 body. None had right side blur so I can rule out problem from my camera, at least at native 12mm and 21mm.
DIGLLOYD: Lens symmetry and skew problems are a widespread issue, particularly with Sony lenses, but it is NOT just a Sony problem; witness the horrific Fujifilm GF 110mm f/2 I received just recently. But I would say that Sony lenses are frequently a source of symmetry issues.
- Sony FE 35mm f/1.4 Distagon ZA Examples at f/1.4, Bad Sample Lens #1, Skew/Asymmetry (Pescadero Creek, A7R)
- Sony FE 35mm f/1.4 Distagon ZA Examples: Bad Sample Lens #2, Skew/Asymmetry (A7R II)
- Shootout vs Zeiss Loxia 50/2: Spuller Lake View to Mt Conness (Sony A7R II)
- Sony 90mm f/2.8 Macro G OSS Examples: Bad Lens Sample (A7R II)
Most symmetry issues go undetected because most shooters stop down and thus mask the issue, shrugging off small differences. Moreoever, most images are not of planar subjects. But the key areas that matter are straight-on shots of buildings, groups of people, distant landscape scenes, and similar.
It can be possible for a lens mount to be warped (even 10 microns is a problem) and thus cause blur on one side or corner. To rule that out, shoot known-good lens. If there is no problem, then that implicates the lens in question. The Sony A7R had a weak lens mount; the A7R II is far better.
Below, favorite target of mine is the mosaic as shown below. I can sight down the center line and shoot at 90° to the mosaic. This target is merciless in revealing all lens weaknesses or asymmetries and/or field curvature and distortion too.