Canon RF 28mm f/2.8 STM vs Canon RF-S 10-18mm f/4.5-6.3 IS STM

These cover different focal lengths — the Canon RF 28mm f/2.8 STM is 28mm, 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 28mm f/2.8 STM for standard, the Canon RF-S 10-18mm f/4.5-6.3 IS STM for wide-angle.

Choose the Canon RF 28mm f/2.8 STM 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 need more reach — it goes to 28mm vs 18mm for distant subjects, wildlife and sport. Choose it if you prefer a fast, compact single focal length — a 28mm prime over a zoom. Choose it if you value portability — at 120g (4.2 oz) it's lighter than the 150g (5.3 oz) alternative for travel and all-day carry.

Choose the Canon RF-S 10-18mm f/4.5-6.3 IS STM if you shoot wide — it starts at 10mm vs 28mm for landscapes, interiors and architecture. Choose it if you want one-lens flexibility — a 10-18mm zoom covers what the fixed 28mm can't reframe. Choose it if you like close-focus work — 0.43x magnification vs 0.26x. Choose it if you use filters or shoot video — internal zoom keeps length and balance constant.

Aperture: the Canon RF 28mm f/2.8 STM 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.