Canon
RF 50mm F1.8 STM
Canon RF Mount
The affordable nifty fifty for RF — compact, sharp, and perfect for beginners exploring prime lenses.
$199
Launch priceReleased Nov 2020
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
RF 50mm F1.8 STM is 1.8 years newer.
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Wins
RF 50mm F1.8 STM
Wins
FE 135mm F1.8 GM
4 categories tied
TL;DR — Key differences
- ARF 50mm F1.8 STM has lower Weight (160 g vs 950 g)
- ARF 50mm F1.8 STM has lower Length (41 mm vs 183 mm)
- ARF 50mm F1.8 STM has higher Max magnification (0.25 × vs 0.15 ×)
- ARF 50mm F1.8 STM has lower Diameter (70 mm vs 81 mm)
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 50mm F1.8 STM
- ✓
Weight
160 g vs 950 g — lower is better
- ✓
Length
41 mm vs 183 mm — lower is better
- ✓
Diameter
70 mm vs 81 mm — lower is better
- ✓
Max magnification
0.25 × vs 0.15 × — higher is better
Reasons to choose the FE 135mm F1.8 GM
- ✓
Special elements
Adds Aspherical
- ✓
Weather sealing
Only FE 135mm F1.8 GM supports it
- ✓
Custom function button
Only FE 135mm F1.8 GM supports it
Shared specifications
Max aperture (Wide)
Both f/1.8
Max aperture (Tele)
Both f/1.8
Min focus distance
Both 30 cm
Internal focus
Both support internal focus
Control ring
Both support control ring
Pros & cons at a glance
Editorially curated highlights and trade-offs.
RF 50mm F1.8 STM
Pros
- ✓Incredible value at under $200
- ✓Very compact and lightweight (only 160g)
- ✓Sharp enough for most everyday photography
- ✓Silent STM motor ideal for video
Cons
- –Plastic build feels basic
- –No weather sealing
- –Narrow maximum aperture vs L-series primes
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 F1.8 STM and FE 135mm F1.8 GM at major authorized retailers.
Canon RF 50mm F1.8 STM
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 May 2026.