Canon
RF 50mm F1.2L USM
Canon RF Mount
Flagship RF 50mm f/1.2 L prime with Ring USM, 15-element design, and weather-sealed L-series build.
$2,299
Launch priceReleased Dec 2018
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 50mm F1.2L USM is 6 months newer.
Affiliate disclosure: As an Amazon Associate, Cameraegg earns from qualifying purchases. Cameraegg may also earn commission from B&H links, at no extra cost to you.
Wins
RF 50mm F1.2L USM
Wins
FE 400mm F2.8 GM OSS
Which would you choose?
TL;DR — Key differences
- BFE 400mm F2.8 GM OSS has higher OIS effectiveness (5 stops vs 0 stops)
- ARF 50mm F1.2L USM has lower Min focus distance (40 cm vs 270 cm)
- ARF 50mm F1.2L USM has lower Length (108 mm vs 359 mm)
- ARF 50mm F1.2L USM has lower Weight (950 g vs 2895 g)
- ARF 50mm F1.2L USM has lower Max aperture (Wide) (f/1.2 vs f/2.8)
Key specs at a glance
Size and weight, to scale
📸 Snap this lens size diff to share
RF 50mm F1.2L USM
⌀90 × 108 mm
950 g (2.09 lb / 33.51 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 50mm F1.2L USM is 251mm shorter and 68mm narrower than FE 400mm F2.8 GM OSS.
RF 50mm F1.2L USM is 1945 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 50mm F1.2L USM
- ✓
Special elements
Adds 1 UD, 1 Aspherical
- ✓
Min focus distance
40 cm vs 270 cm — lower is better
- ✓
Length
108 mm vs 359 mm — lower is better
- ✓
Weight
950 g vs 2895 g — lower is better
- ✓
Max aperture (Wide)
f/1.2 vs f/2.8 — lower is better
- ✓
Max aperture (Tele)
f/1.2 vs f/2.8 — lower is better
- ✓
Diameter
89.8 mm vs 158.1 mm — lower is better
- ✓
Max magnification
0.19 × vs 0.16 × — higher is better
Reasons to choose the FE 400mm F2.8 GM OSS
- ✓
Special elements
Adds 3 Fluorite, 1 ED
- ✓
OIS effectiveness
5 stops vs 0 stops — higher is better
- ✓
Optical stabilization
Only FE 400mm F2.8 GM OSS supports it
- ✓
Custom function button
Only FE 400mm F2.8 GM OSS supports it
Shared specifications
Internal focus
Both support internal focus
Weather sealing
Both support weather sealing
Control ring
Both support control ring
Pros & cons at a glance
Editorially curated highlights and trade-offs.
RF 50mm F1.2L USM
Pros
- ✓Stunning sharpness even wide open at f/1.2
- ✓Beautiful, smooth bokeh with 10 rounded aperture blades
- ✓Fast and accurate Dual Pixel AF with Ring USM
- ✓Weather-sealed L-series construction
Cons
- –Heavy for a 50mm prime (950g)
- –Premium price for a single focal length
- –No optical image stabilization
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 50mm F1.2L USM and FE 400mm F2.8 GM OSS at major authorized retailers.
Canon RF 50mm F1.2L USM
Sony FE 400mm F2.8 GM OSS
Affiliate disclosure: As an Amazon Associate, Cameraegg earns from qualifying purchases. Cameraegg may also earn commission from B&H links, at no extra cost to you.
Full specifications
✓ = category winner
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.