These are the best fisheye lenses for astrophotography when you want full-sky coverage for meteor showers, aurora, Milky Way arches, and star-trail time-lapse—with clean point stars, disciplined coma for a fisheye, strong flare control around the moon, and tough coatings that handle dew heaters—and here’s what to look for as you buy: favor fast fisheyes (ƒ1.8–ƒ3.5) with reliable manual focus and minimal sagittal smear near the edges, circular fisheyes for true all-sky (180° in a circle on full-frame) and diagonal fisheyes for edge-to-edge frames you can partially de-fish, close-focus lenses that let you place dramatic foregrounds inches from the dome, and light barrels that won’t fight trackers or timelapse sliders; most fisheyes can’t take front filters, so plan on heater bands and rear/inline ND only if you’re doing day-to-night. Full-frame heroes: Canon EF 8–15mm ƒ4L Fisheye USM and Nikon AF-S 8–15mm ƒ3.5–4.5E (gold-standard circular→diagonal zooms—use 8 mm for all-sky aurora/meteor plates and ~15 mm for diagonal Milky Way arches; excellent coatings for moon/bright star halos), Samyang/Rokinon 12mm ƒ2.8 diagonal fisheye (fast, budget-friendly wide-open stars), Sigma 15mm ƒ2.8 EX diagonal (compact classic with tidy corners stopped a touch), and Nikon 16mm ƒ2.8 Fisheye (venerable diagonal prime that adapts well). APS-C standouts: Tokina AT-X 10–17mm ƒ3.5–4.5 DX and Pentax DA 10–17mm ƒ3.5–4.5 (beloved by nightscape and aurora shooters—compact, sharp by ƒ4–ƒ5.6, huge sky coverage), Samyang 8mm ƒ2.8 UMC Fisheye II (Sony/Fuji APS-C—fast, light, good for handheld aurora), and the Canon/Nikon 8–15s used on crop for diagonal fisheye across most of the range. Micro Four Thirds stars: Olympus M.Zuiko 8mm ƒ1.8 PRO (the low-light king for fisheye astro—useful speed, excellent coma control, weather-sealed) and Panasonic Lumix G 8mm ƒ3.5 (tiny, sharp, budget option); specialty circulars like Laowa 4mm ƒ2.8 (MFT) are perfect for true all-sky meteor/aurora timelapse when you want the horizon in a full circle. Practical buyer tips: if you want one lens that does both circular all-sky and diagonal frames on full-frame, grab an 8–15 and set custom zoom stops for (a) circular without vignette and (b) diagonal edge-fill; if you prioritize speed on FF, the Samyang 12/2.8 is the value pick; on APS-C, the Tokina 10–17 gives unmatched flexibility for meteors and arches; for MFT, the Olympus 8/1.8 is the dawn/dusk and aurora champion—pair it with a reliable heater band; choose rigid adapters (EF→RF/E/Z/L) with zero play for infinity accuracy and pack a spare heater/USB battery for winter nights. Fisheye astro shooting tips: start around ƒ1.8–ƒ3.5, 10–25 s, ISO 3200–6400 (NPF rule is forgiving at fisheye FLs), focus with magnification on a bright star then tape the ring, stop down 1/3–2/3 stop if corners need discipline, and run long bursts for meteor showers (interval 1–2 s gap, hundreds of frames) then composite; for star trails use 20–30 s subs at ISO 800–1600 and stack; for aurora aim near zenith with a circular fisheye and keep exposure 2–6 s at higher ISO to preserve structure; avoid CPLs, keep the hood clean and shaded from oblique moonlight, run a gentle warmth (WB ~3800–4200 K), and use heater bands early to beat dew; for time-lapse, declick/aperture lock if available to prevent flicker, use a sturdy L-bracket, and enable lens compensation off to keep star shapes honest; whether you’re mapping the entire sky in a single frame, catching meteors streaking across constellations, wrapping a Milky Way arch around a mountain silhouette, or building buttery star-trail circles around Polaris, the best fisheye astro choices—8–15 zooms on full-frame, Tokina/Pentax 10–17 on APS-C, and Olympus/Panasonic 8 mm on MFT—deliver huge sky coverage, workable speed, and post-friendly projection so your stars stay crisp, your gradients stay clean, and your night images feel vast and luminous.