Tamron 17-28mm F/2.8 Di III RXD vs Voigtlander NOKTON 40mm f/1.2 Aspherical
The bottom line
These cover different focal lengths — the Tamron 17-28mm F/2.8 Di III RXD is 17-28mm, the Voigtlander NOKTON 40mm f/1.2 Aspherical is 40mm — so they're not really substitutes. Pick by the field of view you actually need: the Tamron 17-28mm F/2.8 Di III RXD for wide-angle, the Voigtlander NOKTON 40mm f/1.2 Aspherical for short-telephoto / portrait.
Choose the Tamron 17-28mm F/2.8 Di III RXD if…
- ✓You shoot wide — it starts at 17mm vs 40mm for landscapes, interiors and architecture.
- ✓You want one-lens flexibility — a 17-28mm zoom covers what the fixed 40mm can't reframe.
- ✓You like close-focus work — 0.19x magnification vs 0.13x.
- ✓You work outdoors — it's weather-sealed against dust and moisture; the other isn't.
Choose the Voigtlander NOKTON 40mm f/1.2 Aspherical if…
- ✓You want more light and background blur — f/1.2 is faster than f/2.8, better for low light and subject separation.
- ✓You need more reach — it goes to 40mm vs 28mm for distant subjects, wildlife and sport.
- ✓You prefer a fast, compact single focal length — a 40mm prime over a zoom.
- ✓You value portability — at 287g (10.1 oz) it's lighter than the 420g (14.8 oz) alternative for travel and all-day carry.
Where they differ
- ›Aperture: the Voigtlander NOKTON 40mm f/1.2 Aspherical opens to f/1.2 vs the Tamron 17-28mm F/2.8 Di III RXD's f/2.8 — more light and shallower depth-of-field.
- ›Focal range: Tamron 17-28mm F/2.8 Di III RXD is 17-28mm, Voigtlander NOKTON 40mm f/1.2 Aspherical is 40mm — different framing and reach.
- ›Type: the Tamron 17-28mm F/2.8 Di III RXD is a zoom (flexible framing), the Voigtlander NOKTON 40mm f/1.2 Aspherical a prime (one focal length, usually brighter and lighter).
- ›Weight: the Voigtlander NOKTON 40mm f/1.2 Aspherical is 287g (10.1 oz) vs 420g (14.8 oz) — you'll feel the difference handheld.
- ›Durability: the Tamron 17-28mm F/2.8 Di III RXD is weather-sealed; the other isn't.
Frequently asked
Is the Tamron 17-28mm F/2.8 Di III RXD or the Voigtlander NOKTON 40mm f/1.2 Aspherical better?
These cover different focal lengths — the Tamron 17-28mm F/2.8 Di III RXD is 17-28mm, the Voigtlander NOKTON 40mm f/1.2 Aspherical is 40mm — so they're not really substitutes. Pick by the field of view you actually need: the Tamron 17-28mm F/2.8 Di III RXD for wide-angle, the Voigtlander NOKTON 40mm f/1.2 Aspherical for short-telephoto / portrait.
Who should choose the Tamron 17-28mm F/2.8 Di III RXD?
Choose the Tamron 17-28mm F/2.8 Di III RXD if you shoot wide — it starts at 17mm vs 40mm for landscapes, interiors and architecture. Choose it if you want one-lens flexibility — a 17-28mm zoom covers what the fixed 40mm can't reframe. Choose it if you like close-focus work — 0.19x magnification vs 0.13x. Choose it if you work outdoors — it's weather-sealed against dust and moisture; the other isn't.
Who should choose the Voigtlander NOKTON 40mm f/1.2 Aspherical?
Choose the Voigtlander NOKTON 40mm f/1.2 Aspherical if you want more light and background blur — f/1.2 is faster than f/2.8, better for low light and subject separation. Choose it if you need more reach — it goes to 40mm vs 28mm for distant subjects, wildlife and sport. Choose it if you prefer a fast, compact single focal length — a 40mm prime over a zoom. Choose it if you value portability — at 287g (10.1 oz) it's lighter than the 420g (14.8 oz) alternative for travel and all-day carry.
What is the main difference between the Tamron 17-28mm F/2.8 Di III RXD and the Voigtlander NOKTON 40mm f/1.2 Aspherical?
Aperture: the Voigtlander NOKTON 40mm f/1.2 Aspherical opens to f/1.2 vs the Tamron 17-28mm F/2.8 Di III RXD's f/2.8 — more light and shallower depth-of-field.
| Product | ||
|---|---|---|
| Optical Design | ||
| Focal Length | 17-28mm | 40mm |
| Lens Type | Zoom | Prime |
| Optical Elements | 13 | 10 |
| Optical Groups | 12 | 8 |
| Aperture & Iris | ||
| Maximum Aperture | f/2.8 | f/1.2 |
| Minimum Aperture | f/22 | f/16 |
| Aperture Blades | 9 | 12 |
| Rounded Aperture | Yes | Yes |
| Coverage & Angle | ||
| Format Coverage | Full-Frame | Full-Frame |
| Lens Mount | Sony E | Sony E |
| Angle of View | 104° – 75° | 57° |
| 35mm Equivalent | − | − |
| Focus | ||
| Autofocus | Yes | No |
| Focus Motor | RXD | − |
| Focus Limiter | No | No |
| AF/MF Switch | Yes | No |
| Min Focus Distance | 19 cm | 40 cm |
| Max Magnification | 0.19x | 0.13x |
| Stabilization & Video | ||
| Optical Stabilization | No | No |
| Aperture Ring | No | No |
| Declickable Aperture | No | No |
| Parfocal | No | No |
| Internal Zoom | No | No |
| General | ||
| Price (MSRP) | $799 | $799 |
| Filter Size | 67mm | 49mm |
| Diameter | 73mm | 63.3mm |
| Length | 99mm | 59mm |
| Weight | 420g (14.8 oz) | 287g (10.1 oz) |
| Weather Sealed | Yes | No |
| Tripod Collar | No | No |
