Canon RF 5.2mm f/2.8 L Dual Fisheye vs Canon RF-S 10-18mm f/4.5-6.3 IS STM
The bottom line
These cover different focal lengths — the Canon RF 5.2mm f/2.8 L Dual Fisheye is 5mm, the Canon RF-S 10-18mm f/4.5-6.3 IS STM is 10-18mm — so they're not really substitutes. Pick by the field of view you actually need: the Canon RF 5.2mm f/2.8 L Dual Fisheye for wide-angle, the Canon RF-S 10-18mm f/4.5-6.3 IS STM for wide-angle.
Choose the Canon RF 5.2mm f/2.8 L Dual Fisheye if…
- ✓You want more light and background blur — f/2.8 is faster than f/4.5, better for low light and subject separation.
- ✓You shoot wide — it starts at 5mm vs 10mm for landscapes, interiors and architecture.
- ✓You prefer a fast, compact single focal length — a 5mm prime over a zoom.
- ✓You work outdoors — it's weather-sealed against dust and moisture; the other isn't.
Choose the Canon RF-S 10-18mm f/4.5-6.3 IS STM if…
- ✓You need more reach — it goes to 18mm vs 5mm for distant subjects, wildlife and sport.
- ✓You're on a budget — $299 vs $2,099 leaves more for other gear.
- ✓You want one-lens flexibility — a 10-18mm zoom covers what the fixed 5mm can't reframe.
- ✓You value portability — at 150g (5.3 oz) it's lighter than the 395g (13.9 oz) alternative for travel and all-day carry.
Where they differ
- ›Aperture: the Canon RF 5.2mm f/2.8 L Dual Fisheye opens to f/2.8 vs the Canon RF-S 10-18mm f/4.5-6.3 IS STM's f/4.5 — more light and shallower depth-of-field.
- ›Focal range: Canon RF 5.2mm f/2.8 L Dual Fisheye is 5mm, Canon RF-S 10-18mm f/4.5-6.3 IS STM is 10-18mm — different framing and reach.
- ›Type: the Canon RF-S 10-18mm f/4.5-6.3 IS STM is a zoom (flexible framing), the Canon RF 5.2mm f/2.8 L Dual Fisheye a prime (one focal length, usually brighter and lighter).
- ›Price: the Canon RF-S 10-18mm f/4.5-6.3 IS STM is $299, $1,800 under the Canon RF 5.2mm f/2.8 L Dual Fisheye.
- ›Close-up: the Canon RF-S 10-18mm f/4.5-6.3 IS STM reaches 0.43x magnification vs 0.03x — more for close-up and macro work.
- ›Weight: the Canon RF-S 10-18mm f/4.5-6.3 IS STM is 150g (5.3 oz) vs 395g (13.9 oz) — you'll feel the difference handheld.
Frequently asked
Is the Canon RF 5.2mm f/2.8 L Dual Fisheye or the Canon RF-S 10-18mm f/4.5-6.3 IS STM better?
These cover different focal lengths — the Canon RF 5.2mm f/2.8 L Dual Fisheye is 5mm, the Canon RF-S 10-18mm f/4.5-6.3 IS STM is 10-18mm — so they're not really substitutes. Pick by the field of view you actually need: the Canon RF 5.2mm f/2.8 L Dual Fisheye for wide-angle, the Canon RF-S 10-18mm f/4.5-6.3 IS STM for wide-angle.
Who should choose the Canon RF 5.2mm f/2.8 L Dual Fisheye?
Choose the Canon RF 5.2mm f/2.8 L Dual Fisheye if you want more light and background blur — f/2.8 is faster than f/4.5, better for low light and subject separation. Choose it if you shoot wide — it starts at 5mm vs 10mm for landscapes, interiors and architecture. Choose it if you prefer a fast, compact single focal length — a 5mm prime over a zoom. Choose it if you work outdoors — it's weather-sealed against dust and moisture; the other isn't.
Who should choose the Canon RF-S 10-18mm f/4.5-6.3 IS STM?
Choose the Canon RF-S 10-18mm f/4.5-6.3 IS STM if you need more reach — it goes to 18mm vs 5mm for distant subjects, wildlife and sport. Choose it if you're on a budget — $299 vs $2,099 leaves more for other gear. Choose it if you want one-lens flexibility — a 10-18mm zoom covers what the fixed 5mm can't reframe. Choose it if you value portability — at 150g (5.3 oz) it's lighter than the 395g (13.9 oz) alternative for travel and all-day carry.
What is the main difference between the Canon RF 5.2mm f/2.8 L Dual Fisheye and the Canon RF-S 10-18mm f/4.5-6.3 IS STM?
Aperture: the Canon RF 5.2mm f/2.8 L Dual Fisheye opens to f/2.8 vs the Canon RF-S 10-18mm f/4.5-6.3 IS STM's f/4.5 — more light and shallower depth-of-field.
| Product | ||
|---|---|---|
| Optical Design | ||
| Focal Length | 5mm | 10-18mm |
| Lens Type | Prime | Zoom |
| Optical Elements | 10 | 12 |
| Optical Groups | 7 | 9 |
| Aperture & Iris | ||
| Maximum Aperture | f/2.8 | f/4.5 |
| Minimum Aperture | f/22 | f/22 |
| Aperture Blades | 6 | 7 |
| Rounded Aperture | No | Yes |
| Coverage & Angle | ||
| Format Coverage | Full-Frame | APS-C |
| Lens Mount | Canon RF | Canon RF |
| Angle of View | 154° | 110° – 76° |
| 35mm Equivalent | − | 16-29mm |
| Focus | ||
| Autofocus | Yes | Yes |
| Focus Motor | Nano USM | STM |
| Focus Limiter | No | No |
| AF/MF Switch | No | No |
| Min Focus Distance | 13 cm | 12 cm |
| Max Magnification | 0.03x | 0.43x |
| Stabilization & Video | ||
| Optical Stabilization | No | No |
| Aperture Ring | No | No |
| Declickable Aperture | No | No |
| Parfocal | No | No |
| Internal Zoom | No | Yes |
| General | ||
| Price (MSRP) | $2,099 | $299 |
| Filter Size | − | 55mm |
| Diameter | 92.1mm | 68.4mm |
| Length | 63.2mm | 48.8mm |
| Weight | 395g (13.9 oz) | 150g (5.3 oz) |
| Weather Sealed | Yes | No |
| Tripod Collar | No | No |
