Canon RF 10-20mm F4 L IS STM vs Canon RF 15-35mm F2.8L IS USM
Canon RF
According to Canon the RF 10-20 f/4 L is the widest autofocus zoom for RF (October 2023) and the first L lens with an STM motor. It has a built-in lens hood and no front thread, so filters go in as gelatin filters at the rear. The RF 15-35 f/2.8 L (2019) is the classic fast wide-angle zoom with an 82 mm screw-on filter. Both are built for full frame and stabilized (around 5 stops each). At 570 g the 10-20 is about 270 g lighter than the 840 g 15-35.
The choice: 5 mm more wide angle and less weight against a stop more light, 35 instead of 20 mm at the long end and regular filters.
Which one suits whom?
- RF 10-20: You want to shoot extremely wide, for example architecture or interiors, and keep the lens light.
- RF 15-35: You need f/2.8 for events, astro or reportage and want to use screw-on filters.
Key differences
- Focal length: 10-20 mm on the Canon RF 10-20mm F4 L IS STM, 15-35 mm on the Canon RF 15-35mm F2.8L IS USM.
- The Canon RF 15-35mm F2.8L IS USM is faster: f/2.8 instead of f/4, about 1 stops more light.
- The Canon RF 10-20mm F4 L IS STM is 270 g lighter (570 g vs 840 g).
- The Canon RF 10-20mm F4 L IS STM is 15 mm shorter.
- The Canon RF 10-20mm F4 L IS STM focuses closer: from 25 cm instead of 28 cm.
Specs side by side
The key specs of both lenses side by side.
| Lens | Canon RF 10-20mm F4 L IS STM | Canon RF 15-35mm F2.8L IS USM |
|---|---|---|
| Focal length | 10-20 mm | 15-35 mm |
| Max. aperture | f/4 | f/2.8 |
| Weight | 570 g | 840 g |
| Filter diameter | – | 82 mm |
| Min. focus distance | 25 cm | 28 cm |
| Length | 112 mm | 127 mm |
| Autofocus | yes | yes |
| Image stabilization | yes | yes |
Size comparison
- Canon RF 10-20mm F4 L IS STM: 112 × 84 mm
- Canon RF 15-35mm F2.8L IS USM: 127 × 89 mm
Side view to the same scale, length × diameter (without lens hood).