Yesterday, I took my relatively new Sigma 150-600mm F5-6.3 DG OS HSM (Contemporary) out for test shooting at a collegiate baseball game yesterday (in Stockton, CA - the West Coast Conference Championship Tourney). This was my first sporting event with the lens. I started with the "silent shutter mode" - left that way from earlier photo sessions. I noticed distortion - see bat detail shown in photo below. When I restored the shutter mode to "normal", the distortion appears to go away. FYI - the Sigma lens and adapter firmware is up-to-date. Compare the two images - do you have any idea as to what might be causing this issue?
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Distorted photo settings:
1/1600 sec
f/6.3
ISO 400
361 mm
Camera: Sony A7R II
Lens: Sigma 150-600mm F5-6.3 DG OS HSM (Contemporary) - Canon Mount
Lens Adapter: Sigma MC-11
Shutter: Silent Mode
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Normal photo settings:
1/1600 sec
f/6.3
ISO 400
374 mm
Camera: Sony A7R II
Lens: Sigma 150-600mm F5-6.3 DG OS HSM (Contemporary) - Canon Mount
Lens Adapter: Sigma MC-11
Shutter: Normal Single Shot Mode