| Attribute | Value |
|---|---|
| Lens Construction | 13 elements in 11 groups, including 2 aspherical elements |
| Diameter | 88.6 mm |
| Diagonal Angle of View | 94.50 degree |
| Aperture | 1.80 - 22.00 f |
| Notes | Available AF Mounts: Sigma, Canon, Nikon, Minolta, Pentax |
| Filter Size | 82 mm |
| Magnification Ratio | 0.25 x |
| Closest Focus | 0.2 m |
| Focus Details | Internal (Rear Focus) with Dual Focus mechanism |
| Length | 89.5 mm |
| Diaphragm Blades | 9 |
| APS Equivalent | 1.5x: 30mm; 1.6x: 32mm |
| Focal Length | 20.00 mm |
| Image Circle | 35mm |
| Brand | Sigma |
| Name | Sigma 20mm f/1.8 EX DG Aspherical RF |
| Weight | 520 g |
| Type | Wide Prime |
| 35mm Equivalent | Add |
| Effective Reduction in Aperture | Add |
| Focal Length Multiplier | Add |
| APS-C Equivalent | Add |
| Zoom System | Add |
| Diaphragm Blades Type | Add |
| Front Element Rotation | Add |