These are the best Sigma fisheye lenses when you want bold 180° perspectives, close-focus drama, and predictable projection for action, interiors, creative portraits, and VFX plates—and here’s what to look for as you buy: decide on projection first (diagonal fisheye fills the frame vs circular fisheye that renders a round image), match sensor coverage (full frame vs APS-C) so you actually get the look you intend, check whether the hood is removable (useful for near-circular tricks on some bodies), favor lenses with very close minimum focus for exaggerated foregrounds, evaluate flare control and contrast around point lights, consider filter workflow (most fisheyes need rear gel slots or holders—front screw-ins are rare), and if you plan to de-fish, pick optics with consistent edge sharpness; video shooters should consider breathing, smooth focus throw, and rig clearance for that bulbous front. The modern flagship for full-frame diagonal coverage is the Sigma 15mm f/1.4 DG DN Diagonal Fisheye | Art (E/L): blazing fast for night scenes and indoor action, crisp across the frame when stopped a touch, robust Art-series build, and close focus that invites CFWA (close-focus wide-angle) compositions—great for astro arches, skate, and dramatic interiors. For classic full-frame circular effects, the Sigma 8mm f/3.5 EX DG Circular Fisheye paints a clean, round image with mapped 180° coverage—perfect for planet panoramas, scientific work, or stylized transitions—while the Sigma 15mm f/2.8 EX DG Diagonal Fisheye remains a lightweight, budget-friendly full-frame diagonal option on the used market with lively sunstars and quick handling. APS-C shooters have two purpose-built choices: the Sigma 10mm f/2.8 EX DC Fisheye (diagonal fisheye that fills the frame with ~180° on crop, sharp and travel-light for real estate creativity and action cams) and the Sigma 4.5mm f/2.8 EX DC HSM Circular Fisheye (circular projection on APS-C for VR plates, dome work, and unique social cuts). Legacy variants like the older 8mm f/4 (FF circular) also pop up used and adapt well to mirrorless with simple EF-to-E/L/Z adapters. Practical buyer tips: choose diagonal 15mm when you want maximum drama that still grades like a normal frame, circular 8mm/4.5mm when you want the round “porthole” look or need full-hemisphere capture, and 10mm DC for an APS-C one-lens solution; budget for a rear-gel ND or a 100mm holder if you need filtration, verify hood removability before committing to creative edge tricks, and test your copy for infinity accuracy if you’ll shoot stars. Shooting tips: get inches from your subject for maximum curve, keep horizons centered for balanced distortion (tilt deliberately to exaggerate), stop to f/5.6–f/8 to tighten corners, shade that front dome to prevent veiling flare, bracket exposures against bright windows, and de-fish selectively in post when you need straight verticals without losing that signature fisheye energy. Whether you’re wrapping a tiny room into one frame, crafting planet-style transitions, or mapping the Milky Way in a single sweep, the best Sigma fisheye lenses combine dramatic geometry, close-focus fun, and dependable optics—so your images feel big, stylized, and ready to wow.