Sigma 879954
The Sigma TC-1401 is a 1.4x teleconverter for Canon EF mounts, adding 1.4x magnification to compatible lenses while maintaining a compact 190g build and weather sealing. It works with 7 elements in 5 groups, including one ED glass element, and is priced for budget-conscious photographers seeking extra reach. Best for street and portrait shooters who want a lightweight, sealed teleconverter for their existing Canon lenses, though macro work is its weakest area.
No current retailer price
Snapshot
The 30-Second Version
The Sigma 728E01 has excellent build quality at the 91st percentile and weather sealing, but the optical performance is a disappointing 19th percentile. At USD 328, it's a tough sell when competitors offer better versatility and stabilization. The listing is confusing, possibly mixing up a teleconverter and a lens.
Pros & Cons
Pros
- Build quality is top-tier at the 91st percentile 91st
- Weather sealed, which is rare at this price point 71st
- Lightweight at just 190g 70th
- f/1.4 min aperture is above average at the 69th percentile
- 4.5/5 customer rating from early buyers
Cons
- Optical performance is a weak spot at the 19th percentile
- Macro capability is nearly dead last at the 13th percentile
- No stabilization, ranking 35th percentile
- Versatility is limited at the 34th percentile
- Social proof is thin at the 27th percentile with only 4 reviews
The proof
Performance
Let's talk about what this thing actually is. The optical score is 19th percentile, which puts it near the bottom of our database. A 1mm focal length with 7 elements in 5 groups and one ED element sounds more like a spec sheet typo than a real optical design. The aperture ranking is decent at the 69th percentile, but without a max aperture listed, we can't tell you how bright this lens actually gets. Autofocus sits at the 54th percentile, right in the middle, and there's no stabilization, which lands it at the 35th percentile. For a telephoto, that's a problem.
Specifications
Full Specifications
Optics
| Type | Telephoto |
| Focal Length Min | 1 |
| Focal Length Max | 1 |
| Elements | 7 |
| Groups | 5 |
| ED Elements | 1 |
Aperture
| Min Aperture | f/1.4 |
Build
| Mount | Canon EF |
| Weather Sealed | Yes |
| Weight | 0.2 kg / 0.4 lbs |
Focus
| Max Magnification | 1.4x |
vs Competition
Against the competition, the Sigma 728E01 struggles. The Tamron Di III VC 28-300mm f/4-7.1 offers real versatility with its zoom range and VC stabilization. The Sony E 18-135mm f/3.5-5.6 OSS brings optical stabilization and a practical focal range. The Viltrox AF 20mm F2.8 FE is a proper prime with a usable focal length. Even the Nikon NIKKOR 2178 and Panasonic Leica DG Vario-Elmarit H-ES12035 offer more practical everyday use. The Sigma's build quality beats most of these, but build quality doesn't take photos.
| Spec | Sigma 879954 | Tamron Di III VC 28-300mm f/4-7.1 VXD | Nikon NIKKOR 20059 | Panasonic Leica DG Vario-Elmarit H-ES12035 | Sony E 18-135mm f/3.5-5.6 OSS | Canon RF 28-70mm f/2.8 IS STM |
|---|---|---|---|---|---|---|
| Focal Length | 1mm | 28-300mm | 18-55mm | 12-35mm | 18-135mm | 28-70mm |
| Max Aperture | - | f/4 | f/3.5 | f/2.8 | f/3.5 | f/2.8 |
| Mount | Canon EF | Sony E | Nikon F | Micro Four Thirds | Sony E | Canon RF |
| Stabilization | false | true | true | true | true | true |
| Weather Sealed | true | true | false | true | false | true |
| Weight (g) | 190 | 590 | 205 | 306 | 326 | 495 |
| AF Type | - | VXD linear motor | pulse stepping motor | Autofocus | Linear motor | STM |
| Lens Type | telephoto | zoom | zoom | zoom | zoom | zoom |
| Compare | Compare | Compare | Compare | Compare |
| Product | AF | Bokeh | Build | Macro | Optical | Aperture | Versatility | Social Proof | Stabilization |
|---|---|---|---|---|---|---|---|---|---|
| Sigma 879954 | 53.9 | 69.8 | 90.7 | 12.1 | 17.4 | 70.9 | 33.2 | 27.2 | 34.4 |
| Tamron Di III VC 28-300mm f/4-7.1 VXD Compare | 97.7 | 83.4 | 62.9 | 83.2 | 96.3 | 70.9 | 97.9 | 50.4 | 79.3 |
| Nikon NIKKOR 20059 Compare | 84.6 | 81.2 | 83.6 | 95.3 | 54.4 | 82.6 | 82.7 | 86.1 | 92.3 |
| Panasonic Leica DG Vario-Elmarit H-ES12035 Compare | 53.9 | 86.6 | 83.8 | 48.8 | 86.1 | 88.2 | 80.4 | 86.1 | 96.4 |
| Sony E 18-135mm f/3.5-5.6 OSS Compare | 97.7 | 81.2 | 70.9 | 37.3 | 78 | 82.6 | 95.8 | 90.7 | 79.3 |
| Canon RF 28-70mm f/2.8 IS STM Compare | 84.6 | 86.6 | 70.4 | 41.4 | 83.9 | 88.2 | 76.9 | 53.4 | 98.4 |
Price
Value & Pricing
At USD 328 from a single US listing, the value proposition is murky. The build quality is genuinely impressive, and weather sealing at this price is uncommon. But you're paying for a lens with bottom-tier optical scores and no stabilization. The retailer notes mention a Sigma 1.4x Teleconverter TC-1401 for Canon, which suggests this listing might actually be for a teleconverter rather than a lens. If that's the case, USD 328 for a teleconverter is a different conversation entirely.
Read more
Overview
The Sigma 728E01 is a weird one. It's listed as a 1mm f/1.4 prime, which is not a real lens anyone would buy for photography. The specs read more like a database entry gone sideways, mixing up a teleconverter, a lens hood, and a telephoto lens. The build quality sits at the 91st percentile, which is genuinely impressive, and the f/1.4 min aperture lands at the 69th percentile. But the optical score is rough, 19th percentile, and macro performance is nearly dead last at the 13th percentile.
Common Questions
Q: Is this actually a 1mm lens?
The specs list a 1mm focal length, which is extremely unusual for a telephoto lens. The retailer notes reference a Sigma 1.4x Teleconverter TC-1401 for Canon, so this listing may actually be for a teleconverter rather than a standalone lens. We'd recommend confirming with the seller before purchasing.
Q: Does this lens have image stabilization?
No, there's no stabilization built in. This puts it at the 35th percentile compared to other telephoto lenses in our database. For handheld shooting at longer focal lengths, you'll want a camera body with in-body stabilization or a tripod.
Q: How does the optical quality compare to other telephoto lenses?
The optical score sits at the 19th percentile, which is near the bottom of our database. With 7 elements in 5 groups and one ED element, the design is basic. The f/1.4 min aperture is above average at the 69th percentile, but without a listed max aperture, it's hard to judge overall light gathering.
Who Should Skip This
Skip this if you need a real telephoto lens. The optical performance at the 19th percentile is a dealbreaker for anyone serious about image quality. The lack of stabilization at the 35th percentile makes handheld shooting difficult. And the macro score of 17.6/100 means close-up work is essentially off the table. If you're shopping for a teleconverter, make sure this listing is actually for the TC-1401 and not a mismatched product page.
Verdict
The Sigma 728E01 is a confusing product. The 91st percentile build quality and weather sealing are real strengths, and the 4.5/5 rating from the few buyers who got one is encouraging. But the 19th percentile optical score and 13th percentile macro performance are hard to ignore. If you're looking for a telephoto lens, this isn't it. If you're looking for a teleconverter, the listing might actually be for the TC-1401, which is a different product entirely. Either way, we'd recommend checking what's actually in the box before you buy.