See my reviews of Sigma DG HSM Art lenses at 20mm, 24mm, 35mm, 50mm and more.
This aperture series from f/4 through f/11 shows the total imaging quality of the Sigma 12-24mm f/4 DG HSM Art. The behavior is complex, and so this series should be of keen interest to anyone considering the Sigma 12-24/4.
A key aspect of image quality in practice is focus placement in a scene. This implies both that the photographer place focus wisely, including anticipating and compensating for a lens with focus shift, which requires special care based on the shooting aperture. This series discusses what is required for the Sigma 12-24/4.
Includes images up to 28 megapixels along with many large crops, all from f/4 through f/11.
Never before have I been in Yosemite and experienced October temperatures a month later in mid-November. Not only would there usually not be water here, if it were here it would be solid ice. The heavy snows in October were followed by very warm temperatures in November, and this has resulted in very high flows approaching that of late spring, at least in this area. This is just a minor drainage usually containing water only in the spring. All over the area, evidence of very heavy overflows abounds, even here it can be seen that the water was much higher—and normally it is bone-dry. The trout are swimming around in the main creek very happily.
Lakes at 10,000 feet are open and clear; I have seen deep lakes with 18-inch-thick ice at earlier dates! Yet the perimeter of Saddlebag Lake and Ellery Lake have barely a trace of ice. Temperatures at night are running 15°F warmer than I had expected, allowing me snow-free access into this area at ~8200 feet elevation.