Sigma 15mm F1.4 DG DN Diagonal Fisheye | Art (L-Mount)

Sigma calls this the first F1.4 diagonal fisheye for full-frame. It covers 180° corner to corner while filling the whole rectangular frame, and it was designed for star fields and night landscapes where the fisheye curve is part of the picture. Its 21 elements in 15 groups include four FLD, three SLD and two aspherical elements, and sagittal coma flare is corrected so point lights stay tight across the frame.

It shares the astro feature set of Sigma's F1.4 wide primes: an MFL switch that locks the focus ring, a lens-heater retainer, a rear sheet-filter holder, a locking cover cap with two filter slots, and a detachable Arca-Swiss-compatible tripod socket. There is also an HLA linear AF motor, an AFL button, an aperture ring with lock and click switches, and dust and splash sealing. The L-Mount version is 157.9mm long and weighs 1,360g. The fixed petal hood rules out screw-in filters.