I did lighten the extreme corners on both lenses using the manual vignette slider in LR's Lens Correction Tab and maybe a bit more so on the Sigma to help view the extreme corner sharpness easier. Other than that these are straight out of the camera in LR with no profile applied to either lens (the Sigma doesn't have one yet). The overall lighting was pretty good for this type of testing as it remained fairly steady with light overcast skies. Default sharpening Amount=40, Radius=1.0, Detail=25, Masking=0.
Overall the Sigma is not as sharp in the extreme corners at f/2.8 and f/4, but by f/5.6 it catches up to nearly as sharp as the 24mm GM and at f/8 and f/11 it is as good. In fact, at f/11 the Sigma looks a tad sharper as diffraction seems to present itself in the 24mm GM and not as noticeable in the Sigma.
I would have no problem using the Sigma for serious landscape work at apertures in the f5.6 through f/11range in all the focal lengths from 14 to 24mm. The 24mm GM however is still the low light and astro king at f/1.4 - f/5.6.
I ran another series of infinity tests on the Sigma for 14mm, 15mm, 16mm and 18mm. The results of the 14mm and 15mm are really amazing from f/2.8 through f/11. I confirmed again that the Sigma's results vs my Batis 18. The Batis 18 and Sigma are on par in the Center and Mid frame from f/2.8 through f/11, but the Batis 18 has a slight edge in the extreme corners at f/2.8 through f/5.6.
Sep 06, 2019 at 05:24 PM
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