https://opticandframe.com/lenses/feed.xml Optics worth knowing: lens design, character, rendering, and the glass that defines a system. en https://opticandframe.com/lenses/engineering-premium-camera-lenses/ https://opticandframe.com/lenses/engineering-premium-camera-lenses/ Wed, 07 Oct 2026 12:00:00 +0000 Apochromatic correction, aspherical surfaces, floating elements. What those terms actually mean, and why the finest lenses are exercises in controlled obsession. https://opticandframe.com/lenses/what-makes-leica-noctilux-distinctive/ https://opticandframe.com/lenses/what-makes-leica-noctilux-distinctive/ Wed, 07 Oct 2026 12:00:00 +0000 Sixty years, four optical formulas, one idea: a 50mm lens that sees in the dark. The history and character of Leica's fastest nameplate. https://opticandframe.com/lenses/role-of-optical-glass-in-modern-lenses/ https://opticandframe.com/lenses/role-of-optical-glass-in-modern-lenses/ Wed, 07 Oct 2026 12:00:00 +0000 Before a lens is designed, the glass must exist. How a handful of glassmakers, and one 1884 partnership in Jena, still shape what lenses can do. https://opticandframe.com/lenses/sigma-20-60mm-f2-8-4-dg-contemporary/ https://opticandframe.com/lenses/sigma-20-60mm-f2-8-4-dg-contemporary/ Wed, 07 Oct 2026 12:00:00 +0000 The new Contemporary zoom opens at 20mm, weighs 385 grams, focuses to 15.8 centimeters and costs $849. Sigma's answer to the kit lens has arrived.