Canon
RF 70-200mm F2.8L IS USM
Canon RF Mount
An incredibly compact, extending telephoto zoom with L-series optics and 5 stops of stabilization.
$2,799
Launch priceReleased Oct 2019
Tamron
17-70mm F2.8 Di III-A VC RXD
Sony E Mount
17-70mm F2.8 Di III-A VC RXD — 17–70mm f/2.8 for Sony E, a popular choice in the tamron lineup.
$899
Launch priceReleased Jan 2021
17-70mm F2.8 Di III-A VC RXD is 1.3 years newer.
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Wins
RF 70-200mm F2.8L IS USM
Wins
17-70mm F2.8 Di III-A VC RXD
3 categories tied
TL;DR — Key differences
- B17-70mm F2.8 Di III-A VC RXD has lower Weight (525 g vs 1070 g)
- B17-70mm F2.8 Di III-A VC RXD has lower Min focus distance (38 cm vs 70 cm)
- B17-70mm F2.8 Di III-A VC RXD has lower Diameter (65 mm vs 90 mm)
- B17-70mm F2.8 Di III-A VC RXD has lower Length (124 mm vs 146 mm)
- B17-70mm F2.8 Di III-A VC RXD has higher Max magnification (0.25 × vs 0.23 ×)
Key specs at a glance
Use-case scoring
Which one for what?
Algorithmic scores from verified specs · 10 = best in class
Why pick one over the other
Reasons to choose the RF 70-200mm F2.8L IS USM
- ✓
Special elements
Adds 1 Super UD, 1 UD, 2 Aspherical
- ✓
Control ring
Only RF 70-200mm F2.8L IS USM supports it
Reasons to choose the 17-70mm F2.8 Di III-A VC RXD
- ✓
Special elements
Adds Aspherical
- ✓
Weight
525 g vs 1070 g — lower is better
- ✓
Internal focus
Only 17-70mm F2.8 Di III-A VC RXD supports it
- ✓
Min focus distance
38 cm vs 70 cm — lower is better
- ✓
Diameter
65 mm vs 90 mm — lower is better
- ✓
Length
124 mm vs 146 mm — lower is better
- ✓
Max magnification
0.25 × vs 0.23 × — higher is better
Shared specifications
Max aperture (Wide)
Both f/2.8
Max aperture (Tele)
Both f/2.8
Optical stabilization
Both support optical stabilization
OIS effectiveness
Both 5 stops
Weather sealing
Both support weather sealing
Pros & cons at a glance
Editorially curated highlights and trade-offs.
RF 70-200mm F2.8L IS USM
Pros
- ✓Unbelievably compact storage size thanks to extending barrel
- ✓Very lightweight design (only 1070g)
- ✓Excellent center sharpness at all focal lengths
- ✓Dual Nano USM focus motors offer fast, silent AF
- ✓Exceptional 5-stop optical image stabilization
Cons
- –Extending barrel can draw in dust/moisture over time
- –Not compatible with RF teleconverters (due to rear element position)
- –Vignetting is quite heavy wide open
17-70mm F2.8 Di III-A VC RXD
Pros
- ✓Versatile zoom range covers multiple focal lengths in one lens
- ✓Built-in optical image stabilization
- ✓Weather-sealed construction for outdoor shooting
Cons
- –Third-party or older alternatives may offer better value
Decided which one is right for you?
Compare live prices for the RF 70-200mm F2.8L IS USM and 17-70mm F2.8 Di III-A VC RXD at major authorized retailers.
Canon RF 70-200mm F2.8L IS USM
Tamron 17-70mm F2.8 Di III-A VC RXD
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Full specifications
✓ = category winner
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.