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60MP Sony A7R IV
Sigma FE 85mm f/1.4 DG DN Art

Distortion Correction Impact on Micro Contrast and Sharpness

This page looks at how much distortion correction for the pincushion distortion of the Sigma FE 85mm f/1.4 DG DN Art affects micro contrast.

The issue with distortion correction for pincushion distortion is that the pixels must be stretched apart by the greatest amount in the central area of the frame. The center is the most important area, so it’s an awful design decision as compared to distortion correction for barrel distortion, which compresses pixels in the center of the frame and stretches-apart pixels in the outer zones—generally far less important. But as a rule, all moderate telephotos have pincushion distortion to some degree.

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Built-in lens profile does not correct hideous pincushion distortion — approximate manual correction shown
Variants Uncorrected,Corrected available in full article

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