Tamron 70-300mm F/4.5-6.3 Di III RXD vs Sony FE 100-400mm F4.5 GM OSS
Both are Sony E telephoto zoom lenses for full frame. Here is what actually differs.
Pick the Tamron 70-300mm F/4.5-6.3 Di III RXD if
- You want the lighter lens to carry: 1295 g lighter (545 g vs 1840 g)
- You want a wider view: 70mm vs 100mm at the wide end
- You want a compact lens: 148 mm vs 328 mm long
- Our notes say it suits: Casual wildlife, sports in daylight, travel
Pick the Sony FE 100-400mm F4.5 GM OSS if
- You need more reach: 400mm vs 300mm at the long end
- You shoot handheld in dim light or video: it has optical image stabilization and the Tamron 70-300mm F/4.5-6.3 Di III RXD does not
- You shoot close-ups: it focuses down to 0.64 m vs 0.8 m
- You want bigger close-ups: 0.25× vs 0.2× maximum magnification
- You prefer a newer design: released 2026 vs 2020
Spec differences
14 differences| Tamron 70-300mm F/4.5-6.3 Di III RXD | Sony FE 100-400mm F4.5 GM OSS | |
|---|---|---|
| Brand |
Tamron
|
Sony
|
| Focal length |
70-300mm
|
100-400mm
|
| Weight |
545 g
lighter
|
1840 g
|
| Length |
148 mm
shorter
|
328 mm
|
| Diameter |
77 mm
slimmer
|
119.8 mm
|
| Filter thread |
67 mm
|
95 mm
|
| Min focus distance |
0.8 m
|
0.64 m
closer
|
| Max magnification |
0.2×
|
0.25×
larger
|
| Aperture blades |
7
|
not listed
|
| Optical design |
15 elements / 10 groups
|
not listed
|
| Autofocus motor |
RXD
|
not listed
|
| Image stabilization |
No
|
Yes
stabilized
|
| Weather sealing |
Yes
|
not listed
|
| Released |
2020
|
2026
|
4 identical specs hidden: mount, type, format, max aperture. Show all
- Mount
- Sony E both
- Type
- Telephoto Zoom both
- Format
- Full frame both
- Max aperture
- f/4.5 both
Our notes
Tamron 70-300mm F/4.5-6.3 Di III RXD
Compact telephoto zoom for Sony full-frame covering 70-300mm. It has no stabilization and weighs about 545 g.
Pros
- Light at about 545 g
- Compact
- RXD focus motor
Cons
- No lens stabilization
- Slow aperture
Our notes
Sony FE 100-400mm F4.5 GM OSS
More comparisons
Sony E 55-210mm F4.5-6.3 OSS vs Tamron 70-300mm F/4.5-6.3 Di III RXD
200 g lighter vs more reach (300mm)
Tamron 50-400mm F4.5-6.3 Di III VC VXD vs Sony FE 100-400mm F4.5 GM OSS
685 g lighter vs newer (2026)
Sony E 70-350mm F4.5-6.3 G OSS vs Tamron 70-300mm F/4.5-6.3 Di III RXD
more reach (350mm) vs 80 g lighter
Tamron 70-300mm F/4.5-6.3 Di III RXD vs Sigma 100-400mm f/5-6.3 DG DN OS Contemporary
⅓ stop faster vs more reach (400mm)
Sony FE 100-400mm F4.5 GM OSS vs Sigma 100-400mm f/5-6.3 DG DN OS Contemporary
⅓ stop faster vs 700 g lighter
Tamron 70-300mm F/4.5-6.3 Di III RXD vs Sigma 150-600mm f/5-6.3 DG DN OS Sports
⅓ stop faster vs more reach (600mm)