HDRIs of various landscapes such as mountains, deserts, and forests.
12:00, Spring, sunny. Small forest clearing with fresh grass.
Sun is unclipped, so in Cycles, you don't need any light source, other than this HDRI for realistic shadows.
Camera background photos and color-graded JPG panorama: https://photos.app.goo.gl/M5yk5ZycqxuY2znw8
Methodology: 7 expositions with 2EV spacing + 10 expositions of only the sun with ND4096 (12 stop) filter.