I photographed the morning twilight from my property in Santa Fe, New Mexico and was pleased to see these Kelvin-Helmholtz wave clouds for a brief moment.

Canon 7D2 with 100-400 mm EF L lens. 7 exposure bracket centered at 1/500 sec, f/13, ISO 800 with each exposure 1EV apart. Tripod used with 2-second timer delay

Lightroom 7 exposure HDR followed by noise reduction using Topaz Denoise AI