Sigma EX DC HSM 4.5mm f/2.8 5mm
The fast f/2.8 aperture and 180-degree circular projection on APS-C sensors make this a specialized tool for low-light scenarios like astrophotography. Its equisolid angle projection method provides quantifiable data for scientific use, while the HSM motor enables quiet autofocus with full-time manual override. This lens is best for aurora photographers and researchers needing precise solid angle measurements of sky or vegetation distribution.
Snapshot
What owners think
How owner sentiment changed over time
ExclusiveBased on when customers actually wrote their reviews - so you can see whether early praise held up.
Based on 13 dated customer reviews, grouped by calendar quarter. Period analysis is in English.
The proof
Performance
Specifications
Full Specifications
Optics
| Type | Fisheye |
| Focal Length Min | 4 |
| Focal Length Max | 4 |
| Coating | Super Multi-Layer Coating |
Aperture
| Max Aperture | f/2.8 |
| Min Aperture | f/2.8 |
| Constant | Yes |
Build
| Mount | Canon EF |
| Format | APS-C |
| Weight | 0.5 kg / 1.0 lbs |
AF & Stabilization
| AF Type | HSM |
| Stabilization | No |
Focus
| Min Focus Distance | 135 |
| Max Magnification | 1:6 |
vs Competition
| Spec | Sigma EX DC HSM 4.5mm f/2.8 5mm | Tamron Di III 17-70mm f/2.8 Di III-A VC RXD | Nikon NIKKOR Z 17-28mm f/2.8 | Panasonic Leica DG Vario-Elmarit H-ES12035 | Sony E PZ 16-50mm f/3.5-5.6 OSS | Canon RF 28-70mm f/2.8 IS STM |
|---|---|---|---|---|---|---|
| Focal Length | 4mm | 17-70mm | 17-28mm | 12-35mm | 16-50mm | 28-70mm |
| Max Aperture | f/2.8 | f/2.8 | f/2.8 | f/2.8 | f/3.5 | f/22 |
| Mount | Canon EF | Sony E | Nikon Z | Micro Four Thirds | Sony E | Canon RF |
| Stabilization | false | true | false | true | true | true |
| Weather Sealed | false | true | true | true | true | true |
| Weight (g) | 472 | 544 | 450 | 306 | 107 | 495 |
| AF Type | HSM | RXD | Stepping Motor | Autofocus | Autofocus | STM |
| Lens Type | fisheye | zoom | zoom | zoom | zoom | zoom |
| Compare | Compare | Compare | Compare | Compare |
| Product | AF | Bokeh | Build | Macro | Optical | Aperture | User Sentiment | Versatility | Social Proof | Stabilization |
|---|---|---|---|---|---|---|---|---|---|---|
| Sigma EX DC HSM 4.5mm f/2.8 5mm | 53.6 | 81.2 | 43.8 | 90.1 | 46.3 | 83.5 | 7.2 | 33.6 | 60 | 37 |
| Tamron Di III 17-70mm f/2.8 Di III-A VC RXD Compare | 53.6 | 86.4 | 69.8 | 85.1 | 91.1 | 83.5 | 63.1 | 89.5 | 85.1 | 82.7 |
| Nikon NIKKOR Z 17-28mm f/2.8 Compare | 87.7 | 86.4 | 76.1 | 85.1 | 88.4 | 83.5 | 90.7 | 68 | 69.4 | 37 |
| Panasonic Leica DG Vario-Elmarit H-ES12035 Compare | 53.6 | 81.2 | 85.9 | 50.7 | 86.8 | 83.5 | 63.1 | 80.4 | 85.1 | 96.9 |
| Sony E PZ 16-50mm f/3.5-5.6 OSS Compare | 53.6 | 74.6 | 98.6 | 43.7 | 69.2 | 76.7 | 63.1 | 83.2 | 80.6 | 93.5 |
| Canon RF 28-70mm f/2.8 IS STM Compare | 87.7 | 23.3 | 72.9 | 79.3 | 86.8 | 20.4 | 98 | 77.4 | 89.6 | 98.6 |