Sigma 17-40mm f/1.8 DC Art Lens vs Sony FE 20mm f/1.8 G
The bottom line
The Sigma 17-40mm f/1.8 DC Art Lens is a zoom (17-40mm) and the Sony FE 20mm f/1.8 G is a 20mm prime. The zoom gives you framing flexibility from one lens; the prime trades that for a fixed focal length that's usually brighter and lighter to carry. Choose flexibility or a fast single focal length.
Choose the Sigma 17-40mm f/1.8 DC Art Lens if…
- ✓You need more reach — it goes to 40mm vs 20mm for distant subjects, wildlife and sport.
- ✓You want one-lens flexibility — a 17-40mm zoom covers what the fixed 20mm can't reframe.
- ✓You use filters or shoot video — internal zoom keeps length and balance constant.
Choose the Sony FE 20mm f/1.8 G if…
- ✓You prefer a fast, compact single focal length — a 20mm prime over a zoom.
- ✓You value portability — at 373g (13.2 oz) it's lighter than the 560g (1.23 lb) alternative for travel and all-day carry.
Where they differ
- ›Focal range: Sigma 17-40mm f/1.8 DC Art Lens is 17-40mm, Sony FE 20mm f/1.8 G is 20mm — different framing and reach.
- ›Type: the Sigma 17-40mm f/1.8 DC Art Lens is a zoom (flexible framing), the Sony FE 20mm f/1.8 G a prime (one focal length, usually brighter and lighter).
- ›Weight: the Sony FE 20mm f/1.8 G is 373g (13.2 oz) vs 560g (1.23 lb) — you'll feel the difference handheld.
Frequently asked
Is the Sigma 17-40mm f/1.8 DC Art Lens or the Sony FE 20mm f/1.8 G better?
The Sigma 17-40mm f/1.8 DC Art Lens is a zoom (17-40mm) and the Sony FE 20mm f/1.8 G is a 20mm prime. The zoom gives you framing flexibility from one lens; the prime trades that for a fixed focal length that's usually brighter and lighter to carry. Choose flexibility or a fast single focal length.
Who should choose the Sigma 17-40mm f/1.8 DC Art Lens?
Choose the Sigma 17-40mm f/1.8 DC Art Lens if you need more reach — it goes to 40mm vs 20mm for distant subjects, wildlife and sport. Choose it if you want one-lens flexibility — a 17-40mm zoom covers what the fixed 20mm can't reframe. Choose it if you use filters or shoot video — internal zoom keeps length and balance constant.
Who should choose the Sony FE 20mm f/1.8 G?
Choose the Sony FE 20mm f/1.8 G if you prefer a fast, compact single focal length — a 20mm prime over a zoom. Choose it if you value portability — at 373g (13.2 oz) it's lighter than the 560g (1.23 lb) alternative for travel and all-day carry.
What is the main difference between the Sigma 17-40mm f/1.8 DC Art Lens and the Sony FE 20mm f/1.8 G?
Focal range: Sigma 17-40mm f/1.8 DC Art Lens is 17-40mm, Sony FE 20mm f/1.8 G is 20mm — different framing and reach.
| Product | ||
|---|---|---|
| Optical Design | ||
| Focal Length | 17-40mm | 20mm |
| Lens Type | Zoom | Prime |
| Optical Elements | 17 | 14 |
| Optical Groups | 11 | 12 |
| Aperture & Iris | ||
| Maximum Aperture | f/1.8 | f/1.8 |
| Minimum Aperture | f/16 | f/22 |
| Aperture Blades | 11 | 9 |
| Rounded Aperture | Yes | Yes |
| Coverage & Angle | ||
| Format Coverage | APS-C | Full-Frame |
| Lens Mount | Sony E | Sony E |
| Angle of View | 76.5° – 37.1° | 94° – 94° |
| 35mm Equivalent | 25-60mm | − |
| Focus | ||
| Autofocus | Yes | Yes |
| Focus Motor | HLA | XD Linear |
| Focus Limiter | No | No |
| AF/MF Switch | Yes | Yes |
| Min Focus Distance | 28 cm | 18 cm |
| Max Magnification | 0.21x | 0.22x |
| Stabilization & Video | ||
| Optical Stabilization | No | No |
| Aperture Ring | Yes | Yes |
| Declickable Aperture | Yes | Yes |
| Parfocal | No | No |
| Internal Zoom | Yes | No |
| General | ||
| Price (MSRP) | $919 | $899 |
| Filter Size | 67mm | 67mm |
| Diameter | 72.9mm | 73.5mm |
| Length | 115.9mm | 84.7mm |
| Weight | 560g (1.23 lb) | 373g (13.2 oz) |
| Weather Sealed | Yes | Yes |
| Tripod Collar | No | No |
