These are the best Sigma wide-angle lenses when you want disciplined geometry, strong flare control, and modern autofocus for landscapes, interiors, architecture, travel, and astro—across full frame and APS-C—and here’s what to look for as you buy: prioritize rectilinear designs with low distortion (clean verticals and easier pano stitching), corner performance at working apertures (f/5.6–f/8 for landscapes; f/2–f/2.8 for nightscapes), coma/astigmatism control if you shoot stars, flare resistance and attractive sunstars (blade shape matters), filter friendliness (front threads vs bulbous fronts that need 100mm holders), quiet AF and minimal breathing if you film, close-focus for foreground layers, weather sealing and sane weight for long hikes, and consistent color across your set (DG DN Contemporary and Art pair well). Full-frame anchors: the 14–24mm f/2.8 DG DN | Art is the bright, corner-clean ultra-wide zoom for interiors, waterfalls, and night skies; the featherweight 16–28mm f/2.8 DG DN | Contemporary is the travel-friendly alternative that still takes 72mm filters; for prime speed and astro discipline, go 14mm f/1.4 DG DN | Art (Milky Way monster with excellent off-axis control), 20mm f/1.4 DG DN | Art (balanced “stars + subject” focal), and 24mm f/1.4 DG DN | Art (environmental night scenes and city blue hour). Prefer tiny, threaded, all-metal walk-around primes? The I-Series 17mm f/4, 20mm f/2, and 24mm f/2 DG DN | Contemporary are pocketable, quiet, and great for travel, with crisp micro-contrast and close-focus for layered foregrounds. Legacy DSLR options that adapt well include the 12–24mm f/4 DG HSM | Art (rectilinear extremes with a huge image circle) and the 14–24mm f/2.8 DG HSM | Art; if you want a wide-normal with speed, the 35mm f/1.4 DG DN | Art pairs nicely for stitched vistas and twilight streets. On APS-C, the 10–18mm f/2.8 DC DN | Contemporary is the new go-to: tiny, fast, threaded for filters, and sharp—perfect for travel and real estate—while the 16mm f/1.4 DC DN | Contemporary remains a legend for handheld blue hour, astro, and gimbals; add the 18–50mm f/2.8 DC DN | Contemporary for lightweight mid-range coverage that color-matches. Practical buyer tips: pick your anchor by subject—14–16mm for maximum drama and tight interiors, ~20mm for balanced foreground/sky and astro, 24–28mm for environmental storytelling and city work; if you love long exposures and grads, favor threaded fronts (16–28 C, 17/4, 20/2, 24/2) or budget for a 100mm holder on bulbous lenses (14–24 A, 14/1.4 A); hikers should weigh the extra stop of the 14–24/2.8 against the carry-everywhere 16–28/2.8; for hybrid shooters, test breathing (DG DN zooms are well-behaved) and keep one fast prime for night. Field tips: use hyperfocal at f/5.6–f/8 for fast ridge shots, shade domed fronts to tame sunballs, bracket exposures for high-contrast windows/skies, stop 1/3–2/3 stop from wide open to tighten corners on fast primes, level the camera and correct perspective lightly in post, and exploit close-focus on I-Series primes to build foreground depth. Whether you’re threading cathedral aisles, mapping the Milky Way at 14–20mm, or flying a gimbal through tight alleys, the best Sigma wide-angle lenses combine clean geometry, flare discipline, and modern, lightweight builds—so you move faster, shoot longer, and bring home files that stitch, grade, and print beautifully.