Sigma Art 17-40mm f/1.8 DC
Canon RF-S 3.9mm f/3.5 STM Dual Fisheye 4mm
What Buyers Say
Sigma Art 17-40mm f/1.8 DC
The Sigma 17-40mm f/1.8 DC DN Art lens is overwhelmingly praised for its exceptional image quality, fast constant aperture, and compact internal zoom design. Users highlight its sharpness, lightweight build, and excellent autofocus performance, especially on crop-sensor mirrorless cameras like the Canon R7 and Fujifilm bodies. A few questions about compatibility with specific cameras and features like weather sealing and aperture ring are noted, but the overall sentiment is extremely positive.
Pros
- Exceptional image quality
- Fast constant f/1.8 aperture
- Compact internal zoom design
- Lightweight build
- Sharp and bright photos
Cons
- No weather sealing mentioned
- No manual aperture ring on some mounts
- Compatibility questions with full-frame cameras
- Expensive for some buyers
Canon RF-S 3.9mm f/3.5 STM Dual Fisheye 4mm
The Canon RF-S 3.9mm f/3.5 STM Dual Fisheye Lens receives mixed feedback. One verified user reports a critical autofocus bug that requires a camera reset to fix, and incompatibility with Canon VR Utility for equirectangular conversion. Another verified owner finds it a good, affordable, lightweight alternative to the Canon R5 setup with autofocus. A third unverified user praises it for VR video, calling it a 10/10 purchase for wedding videography.
Pros
- Affordable alternative to R5 setup
- Lightweight design
- Autofocus capability
- Great for VR video
- Good for wedding videography
Cons
- Frequent autofocus loss requiring camera reset
- Incompatible with Canon VR Utility
- Limited compatibility (only R7 confirmed)
- No screw-on ND filter options
- Autofocus only on left lens subject
Scores
Specifications
| Sigma Art 17-40mm f/1.8 DC | Canon RF-S 3.9mm f/3.5 STM Dual Fisheye 4mm | |
|---|---|---|
| Optics | ||
| Type | zoom | fisheye |
| Focal Length Min | 17 mm | 4 mm |
| Focal Length Max | 40 mm | 4 mm |
| Elements | 17 | 11 |
| Groups | 11 | 8 |
| Aspherical Elements | 4★ | — |
| ED Elements | 4★ | 2 |
| Coating | Super Multi-Layer Coating | Air Sphere Coating |
| Aperture | ||
| Max Aperture | f/1.8 | f/16 |
| Min Aperture | f/1.8 | f/3.5 |
| Constant | ✓★ | ✗ |
| Diaphragm Blades | 11★ | 7 |
| Build | ||
| Mount | Fujifilm X | Canon RF |
| Format | APS-C | APS-C |
| Weather Sealed | ✓★ | ✗ |
| Weight | 0.54 kg | 0.29 kg★ |
| Filter Thread | 67 mm | 31 mm |
| AF & Stabilization | ||
| AF Type | HLA (High-response Linear Actuator) | STM★ |
| Stabilization | ✗ | ✗ |
| Focus | ||
| Min Focus Distance | 280 mm | 201 mm★ |
| Max Magnification | 1:4.8 | 1:33.33 |
Pros & Cons
Sigma Art 17-40mm f/1.8 DC
- Strong user sentiment (98th percentile)98th %ile
- Strong optical (97th percentile)97th %ile
- Strong bokeh (97th percentile)97th %ile
- Strong aperture (95th percentile)95th %ile
Canon RF-S 3.9mm f/3.5 STM Dual Fisheye 4mm
- Strong af (85th percentile)85th %ile
- Strong macro (81st percentile)81st %ile
- Strong build (76th percentile)
- Below average user sentiment (2nd percentile)2nd %ile
- Below average social proof (26th percentile)
- Below average bokeh (30th percentile)
- Below average versatility (34th percentile)
Pricing
Sigma Art 17-40mm f/1.8 DC offers 2.2x better value for money
Verdict
Scores 97 overall, wins 9 of 9 usage categories and 5 of 21 specs.
