Zeiss 25mm f/2 Distagon Field Curvature Study (Yosemite, Tioga)
Published in my Guide to Zeiss ZF / ZE Lenses is what I consider the most instructive study of field curvature that I have yet published, Tioga Lake and Mt Dana with the Zeiss 25mm f/2 Distagon.
I recommend this new field curvature article to anyone seeking maximum image quality (Zeiss user or not), because it shows just how damaging to sharpness a tiny alteration in focus can produce and also how “minimal” field curvature can be a Big Deal.
Side note: I took this image while waiting for better light at dusk. The Nikon D800E is impressive in its usable dynamic range: the quality of the D800E sensor and its 14-bit lossless-compressed NEF files allowed the severe-contrast (almost black foreground) to be brought up. Adobe RAW processing included Highlights = -42, Shadows = +100.
By the way, Mt Dana makes a nice climb. Mt Dana is the peak seen at upper left in the image above.