Ultra-Fast Diagonal Fisheye Prime. The Sigma 15mm f/1.4 DG DN Art for L-Mount’s ultra-fast f/1.4 aperture, 180° angle of view, and exceptional sharpness make it unique among diagonal fisheye lenses. It’s ideal for astrophotography, nightscapes, architectural photography, landscape photography, and any scenario that requires shooting in low light. The main draw of a fisheye lens is its namesake distortion effect, and the 15mm is capable of giving you dramatic, artistic results. The rounded eleven-blade diaphragm helps produce large, pleasing bokeh. Using an APS-C sensor camera? You’ll have a focal length equivalent to 21mm.

Optimized for Astrophotography. In addition to its large maximum aperture, the 15mm f/1.4 has a range of features that make it a fantastic choice for astrophotography. Its optical design and in-camera corrections keep distortion reined in, producing extremely well-controlled sagittal flare that yields pin-point stars from edge to edge while limiting ghosting. A Manual Focus Lock switch disables the focus ring so that your focus never changes even if you’re shooting under the night sky for hours. This lens’s rear filter holder accepts sheet-type filters that are often used by astrophotographers to produce various artistic effects, and there’s a retainer at the front of the lens that eliminates the risk of vignetting and other interference when you’re using a lens heater on lengthy shoots.

Fast, Precise, and Nearly Silent Autofocus. The 15mm’s autofocus system uses a High-Response Linear Actuator motor to provide fast, smooth, and nearly silent performance with minimal focus breathing, making it great for stills and video alike. An AF/MF switch and aperture-ring click switch allow for immediate manual-focus override when you need to make minute adjustments. A built-in Autofocus-Lock button can be assigned additional functions, giving you more options and capabilities, while a Manual Focus Lock feature disables the focus ring entirely.

Optics Built for Sharpness. This lens’s 15-group/21-element optical design includes 2 aspherical elements, 3 Special Low-Dispersion elements, and 4 “F” Low-Dispersion elements to minimize chromatic aberrations, distortion, and vignetting while providing maximum sharpness, color accuracy, and clarity. Each element has a Super Multilayer Coating that helps prevent flare and produce contrasty, color-neutral images, even when you’re shooting in backlit conditions.

Durable, Weather-Resistant Build. The Sigma 15mm’s Thermally Stable Composite build is dust- and splash-resistant, so that you can use it in adverse conditions. It also boasts a brass bayonet mount for maximum durability and precision. An included petal-type hood helps to prevent flare and protect the lens’s front element.