Canon
RF 24-70mm F2.8L IS USM
Canon RF Mount
The cornerstone zoom for Canon mirrorless, featuring 5 stops of optical image stabilization.
$2,399
Launch priceReleased Aug 2019
Sony
FE 400mm F2.8 GM OSS
Sony E Mount
World's lightest 400mm F2.8 — 2895g with 3 fluorite elements, XD Linear AF, and OSS.
$12,000
Launch priceReleased Jun 2018
RF 24-70mm F2.8L IS USM is 1.2 years newer.
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Wins
RF 24-70mm F2.8L IS USM
Wins
FE 400mm F2.8 GM OSS
3 categories tied
Which would you choose?
TL;DR — Key differences
- ARF 24-70mm F2.8L IS USM has lower Min focus distance (21 cm vs 270 cm)
- ARF 24-70mm F2.8L IS USM has lower Weight (900 g vs 2895 g)
- ARF 24-70mm F2.8L IS USM has lower Length (125 mm vs 359 mm)
- ARF 24-70mm F2.8L IS USM has higher Max magnification (0.3 × vs 0.16 ×)
- ARF 24-70mm F2.8L IS USM has lower Diameter (88 mm vs 158.1 mm)
Key specs at a glance
Size and weight, to scale
📸 Snap this lens size diff to share
RF 24-70mm F2.8L IS USM
⌀88 × 125 mm
900 g (1.98 lb / 31.75 oz)
Credit card
85.6 × 54 mm
for scale
FE 400mm F2.8 GM OSS
⌀158 × 359 mm
2895 g (6.38 lb / 102.12 oz)
RF 24-70mm F2.8L IS USM is 234mm shorter and 70mm narrower than FE 400mm F2.8 GM OSS.
RF 24-70mm F2.8L IS USM is 1995 g lighter than FE 400mm F2.8 GM OSS.
Diameter (⌀) is the maximum barrel width; length is measured from the mount to the front of the lens.
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 24-70mm F2.8L IS USM
- ✓
Special elements
Adds 3 Aspherical, 3 UD
- ✓
Min focus distance
21 cm vs 270 cm — lower is better
- ✓
Weight
900 g vs 2895 g — lower is better
- ✓
Length
125 mm vs 359 mm — lower is better
- ✓
Diameter
88 mm vs 158.1 mm — lower is better
- ✓
Max magnification
0.3 × vs 0.16 × — higher is better
Reasons to choose the FE 400mm F2.8 GM OSS
- ✓
Special elements
Adds 3 Fluorite, 1 ED
- ✓
Custom function button
Only FE 400mm F2.8 GM OSS supports it
Shared specifications
Max aperture (Wide)
Both f/2.8
Max aperture (Tele)
Both f/2.8
Internal focus
Both support internal focus
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 24-70mm F2.8L IS USM
Pros
- ✓Built-in optical image stabilization (up to 5 stops)
- ✓Excellent L-series sharpness and build quality
- ✓Fast and silent Nano USM focus motor
- ✓Very low chromatic aberration
Cons
- –Heavier than competitive options (900g)
- –Pricey entry threshold
- –Minor barrel distortion at 24mm
FE 400mm F2.8 GM OSS
Pros
- ✓Prime design typically delivers strong sharpness and lighter weight
- ✓Built-in optical image stabilization
- ✓Weather-sealed construction for outdoor shooting
Cons
- –Premium price point
- –Relatively heavy for extended handheld use
Decided which one is right for you?
Compare live prices for the RF 24-70mm F2.8L IS USM and FE 400mm F2.8 GM OSS at major authorized retailers.
Canon RF 24-70mm F2.8L IS USM
Sony FE 400mm F2.8 GM OSS
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Full specifications
✓ = category winner
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.