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Sigma 50mm f/1.4 DG HSM A

MTF for Sigma 50mm f/1.4 DG HSM A

The MTF chart for f/1.4 shows high central contrast which drops off steadily to the edges and corners. At least at the center, it should perform extremely well, but note that 30 lp/mm (green lines) cannot be compared directly to the 40 lp/mm used in Zeiss and Leica MTF charts, nor is the spectral weighting designated. Moreover, Zeiss charts are measured results from real lenses (not computed idealizations).

The high contrast at full aperture means that correction for both longitudinal chromatic aberration and spherical aberration must be excellent, as discussed.

The drop-off away from center is likely due to increasing aberrations off-center, but it could also be a field curvature effect, probably some of both.

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Diglloyd DAP is DSLR-oriented, but also contains workflow and other topics. Much of the focus is on Canon and Nikon but also Pentax and Pentax medium format.

Special emphasis is placed on lens evaluation, focusing on Canon and Nikon and Sigma lenses, but with a few others like Rokinon/Samyang.

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MTF for Sigma 50mm f/1.4 DG HSM

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