Cameras Ranked

50 Canon RF 50mm F1.8 STM

The Canon RF 50mm F1.8 STM is a prime lens for Canon RF (Full frame) that covers 50 mm at f/1.8, weighs 160 g and focuses as close as 0.3 m. Lightest (160 g) and dimmest (f/1.8) of the 4 full frame Canon RF prime lenses in its focal range. Among them, it suits you if you carry it all day or travel light, or you want to focus closer at the wide end. If you shoot in low light or want a blurrier background, every other one that does better on brightness gives up weight.

  • f/1.8widest aperture
  • 160 gweight
  • 17bodies it fits
To one scale. Canon RF 50mm F1.8 STM: length 40.5 mm, diameter 69.2 mm, filter thread 43 mm.40.5 mmø69.2
To scale from the maker's length and diameter, the mount on the left and the filter thread in yellow at the front. The rings are drawn, not measured.

Compare it with another lensAll Canon RF lenses

To one scale. Canon RF 50mm F1.8 STM: length 40.5 mm, diameter 69.2 mm, filter thread 43 mm.40.5 mmø69.2
To scale from the maker's length and diameter, the mount on the left and the filter thread in yellow at the front. The rings are drawn, not measured.

Where it sits

4 lenses

Full frame Canon RF prime lenses in its focal range that state each value, this one included. Each tick is one; the thick one is this one.

Bodies it fits

17 bodies

All cameras, by maker and mount

Specifications

Focal length
50 mm1
Widest aperture
f/1.82
Closest focus
0.3 m3
Maximum magnification
0.25x3
Stabilization
7 stops (with a EOS R5 or EOS R6)3
Mount
Canon RF3
Covers
Full frame
Type
Prime
Weight
160 g3
Length
40.5 mm3
Diameter
69.2 mm3
Filter thread
43 mm3
On sale from
Dec 20204
Elements
63
Groups
53
Aperture blades
73
Weather sealed
No3
Focus motor
Gear-type Stepping Motor3
Hood
ES-65B (sold separately)3

Sources

  1. www.canon.at, cited by Wikidata for Focal length (Wikidata checked Oct 9, 2026; we didn't read this page)
  2. Wikidata, checked Oct 9, 2026 (CC0 1.0)
  3. Canon product specifications, checked Oct 6, 2026
  4. global.canon, cited by Wikidata for On sale from (Wikidata checked Oct 9, 2026; we didn't read this page)

Worked out by code, not stated by a source

  • Read from the lens name: each maker marks the sensor size a lens covers (Sony FE/E, Canon RF/RF-S, Nikon DX, Tamron Di III/Di III-A, Sigma DG/DC); every Fujifilm X lens is APS-C and every Micro Four Thirds lens is Four Thirds.
  • Read from the lens name: Sony marks optically stabilized lenses OSS, Canon IS, Nikon VR, Fujifilm OIS, Panasonic O.I.S., Tamron VC and Sigma OS; a lens from these makers without the mark has no optical stabilization.
  • Prime or zoom, read from the focal length in the lens name.

Each value is checked automatically against the source it links, on the date shown. How we build these pages

† The makers' own tables, row by row, with labels in our plain words (translated where the maker's page isn't in English); each row's numbers are checked against the page it links.

Full specifications†

Show all 15 rows
Full specificationsCanon RF 50mm F1.8 STM3
Diagonal angle of view46°00′ (Diagonal)
Horizontal angle of view40°00′ (Horizontal)
Vertical angle of view27°30′ (Vertical)
Closest focusing distance0.30 m / 0.98 ft
Lens construction5 groups, 6 elements
Diameter and length69.2 mm x 40.5 mm (Approx.)
Drive system typeGear-type Stepping Motor
Filter size43 mm
Maximum magnification0.25 x
Minimum aperture22
Number of diaphragm blades7
Weight160 g (Approx.)
Included lens capLens cap E-43 & Lens Dust Cap RF (included)
Lens hood modelLens Hood ES-65B (sold separately)
Lens case modelLens Case LP1014 (sold separately)

How the pick works

  1. Widest aperture3

    Lower wins once they are 0.3 apart.

  2. Weight2

    Lower wins from a 12% gap.

  3. Focal length (longest)2

    Higher wins from a 15% gap.

  4. Focal length (widest)2

    Lower wins once they are 2 mm apart.

  5. Optical stabilization1

    Having it wins.

  6. Closest focus, wide end1

    Lower wins from a 15% gap. Compared only between lenses of the same focal length (widest).

  7. Filter thread0.5

    Lower wins once they are 5 mm apart.

  8. Lead for a pick1

Our pick or our take adds up the importance of each real difference, with these importances and thresholds: a gap smaller than its row's threshold is too close to call and counts as the same. They are our editorial choice, not a measurement, the same on every page, and they never read prices, sales or who sells it.

Paid placements0

How we rank, in full