John Riley finds the Sigma 20-200mm f/3.5-6.3 DG Contemporary lens offers incredible versatility and impressiv... John Riley reviews and tests the Sigma 35mm f/1.4 DG II Art Lens, exploring its ...

April 7, 2026 • The astronauts on Artemis II observed parts of the moon humans had never seen before. Their findings provide a scientific baseline — and sense of wonder — for future missions.

Abstract: Mode coupling is a fundamental concept to model and understand light propagation in optical fibers when they are affected by irregularities with respect to an ideal case. This paper reviews ...