Canon
RF 800mm F5.6 L IS USM
Canon RF Mount
800mm super-telephoto with built-in 1.4× extender (1120mm F8) and Dual Nano USM autofocus.
$16,999
Launch priceReleased Apr 2022
Sony
FE 50mm F1.4 GM
Sony E Mount
FE 50mm F1.4 GM — 50mm f/1.4 for Sony E, a popular choice in the sony lineup.
$1,799
Launch priceReleased Mar 2025
FE 50mm F1.4 GM is 2.9 years newer.
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Wins
RF 800mm F5.6 L IS USM
Wins
FE 50mm F1.4 GM
Which would you choose?
TL;DR — Key differences
- ARF 800mm F5.6 L IS USM has higher OIS effectiveness (5.5 stops vs 0 stops)
- BFE 50mm F1.4 GM has lower Min focus distance (30 cm vs 260 cm)
- BFE 50mm F1.4 GM has lower Weight (580 g vs 3140 g)
- BFE 50mm F1.4 GM has lower Max aperture (Wide) (f/1.4 vs f/5.6)
- BFE 50mm F1.4 GM has lower Max aperture (Tele) (f/1.4 vs f/5.6)
Key specs at a glance
Size and weight, to scale
📸 Snap this lens size diff to share
RF 800mm F5.6 L IS USM
⌀163 × 432 mm
3140 g (6.92 lb / 110.76 oz)
Credit card
85.6 × 54 mm
for scale
FE 50mm F1.4 GM
⌀81 × 131 mm
580 g (1.28 lb / 20.46 oz)
RF 800mm F5.6 L IS USM is 301mm longer and 82mm wider than FE 50mm F1.4 GM.
RF 800mm F5.6 L IS USM is 2560 g heavier than FE 50mm F1.4 GM.
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 800mm F5.6 L IS USM
- ✓
Special elements
Adds 2 Fluorite, 2 UD, 1 Aspherical
- ✓
OIS effectiveness
5.5 stops vs 0 stops — higher is better
- ✓
Optical stabilization
Only RF 800mm F5.6 L IS USM supports it
- ✓
Max magnification
0.34 × vs 0.15 × — higher is better
Reasons to choose the FE 50mm F1.4 GM
- ✓
Special elements
Adds Aspherical, ED
- ✓
Min focus distance
30 cm vs 260 cm — lower is better
- ✓
Weight
580 g vs 3140 g — lower is better
- ✓
Max aperture (Wide)
f/1.4 vs f/5.6 — lower is better
- ✓
Max aperture (Tele)
f/1.4 vs f/5.6 — lower is better
- ✓
Length
131 mm vs 432 mm — lower is better
- ✓
Diameter
81 mm vs 163 mm — lower is better
Shared specifications
Internal focus
Both support internal focus
Weather sealing
Both support weather sealing
Control ring
Both support control ring
Custom function button
Both support custom function button
Pros & cons at a glance
Editorially curated highlights and trade-offs.
RF 800mm F5.6 L IS USM
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
- –Slower maximum aperture limits low-light performance
FE 50mm F1.4 GM
Pros
- ✓Bright f/1.4 aperture for low light and subject separation
- ✓Prime design typically delivers strong sharpness and lighter weight
- ✓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 800mm F5.6 L IS USM and FE 50mm F1.4 GM at major authorized retailers.
Canon RF 800mm F5.6 L IS USM
Sony FE 50mm F1.4 GM
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Full specifications
✓ = category winner
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed June 2026.