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 135mm F1.8 GM
Sony E Mount
FE 135mm F1.8 GM — 135mm f/1.8 for Sony E, a popular choice in the sony lineup.
$1,899
Launch priceReleased Feb 2019
FE 135mm F1.8 GM is 2 months newer.
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Wins
RF 50mm F1.2L USM
Wins
FE 135mm F1.8 GM
2 categories tied
Which would you choose?
TL;DR — Key differences
- ARF 50mm F1.2L USM has lower Length (108 mm vs 183 mm)
- ARF 50mm F1.2L USM has lower Max aperture (Wide) (f/1.2 vs f/1.8)
- ARF 50mm F1.2L USM has lower Max aperture (Tele) (f/1.2 vs f/1.8)
- BFE 135mm F1.8 GM has lower Min focus distance (30 cm vs 40 cm)
- ARF 50mm F1.2L USM has higher Max magnification (0.19 × vs 0.15 ×)
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 135mm F1.8 GM
⌀81 × 183 mm
950 g (2.09 lb / 33.51 oz)
RF 50mm F1.2L USM is 75mm shorter and 9mm wider than FE 135mm F1.8 GM.
RF 50mm F1.2L USM and FE 135mm F1.8 GM weigh the same.
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
- ✓
Length
108 mm vs 183 mm — lower is better
- ✓
Max aperture (Wide)
f/1.2 vs f/1.8 — lower is better
- ✓
Max aperture (Tele)
f/1.2 vs f/1.8 — lower is better
- ✓
Max magnification
0.19 × vs 0.15 × — higher is better
Reasons to choose the FE 135mm F1.8 GM
- ✓
Special elements
Adds Aspherical
- ✓
Custom function button
Only FE 135mm F1.8 GM supports it
- ✓
Min focus distance
30 cm vs 40 cm — lower is better
- ✓
Diameter
81 mm vs 89.8 mm — lower is better
Shared specifications
Internal focus
Both support internal focus
Weight
Both 950 g
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 135mm F1.8 GM
Pros
- ✓Prime design typically delivers strong sharpness and lighter weight
- ✓Weather-sealed construction for outdoor shooting
- ✓Native Sony E mount compatibility
Cons
- –Relatively heavy for extended handheld use
- –Third-party or older alternatives may offer better value
Decided which one is right for you?
Compare live prices for the RF 50mm F1.2L USM and FE 135mm F1.8 GM at major authorized retailers.
Canon RF 50mm F1.2L USM
Sony FE 135mm F1.8 GM
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Full specifications
✓ = category winner
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed July 2026.