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Sigma 20mm f/1.4 DG HSM Art Aperture Series: Pescadero Creek (Canon 5DS R)

Sigma 20mm f/1.4 DG HSM Art

Get Sigma 20mm f/1.4 DG HSM Art at B&H Photo.

All wide angle lenses have some degree of field curvature; it is a matter of how much, and it results from the natural Petzval field curvature aspect of optical design. The only question is how the lens design balances the curvature against other design parameters.

This scene shows the practical implications of field curvature with a common type of landscape composition. For the Sigma 20mm f/1.4 DG HSM Art, the behavior demonstrated here is critical to getting the best results from the lens. Thus it is as much a tutorial on technique as it is a lens assessment.

Sigma 20mm f/1.4 DG HSM Art Aperture Series: Pescadero Creek (5DS R)

Includes images up to 24 megapixels as well as large crops, all from f/1.4 through f/13.

As with other recent images, I’m struck by the dramatic difference seen in viewing the images on the late 2015 iMac 5K. The 14.7-megapixel screen delivers an image whose fine detail looks better than and 4 X 5 'chrome' I ever saw: larger, more luminous and absolutely crisp (with good images). Contrast and color saturation are very rich. So much so that my workhorse NEC PA302W looks drab by comparison. Mastering an image for a print may thus make the iMac 5K display not such a good option, but it is sure lovely to look at.

Pescadero Creek after Powerful Rainstorm
f3.2 @ 1/6 sec, ISO 100; 2015-12-25 16:13:45
Canon EOS 5DS R + Sigma 20mm f/1.4 DG HSM Art

[low-res image for bot]
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