Canon RF 100-300mm F2.8L IS USM vs Canon RF 400mm F2.8L IS USM

Two f/2.8 L telephotos for Canon RF, both stabilized (up to 5.5 stops), dust and water resistant and compatible with the RF 1.4x and 2x extenders. The RF 400 f/2.8 L (July 2021) is the classic super-tele prime at 2.9 kg and 367 mm long. The RF 100-300 f/2.8 L (May 2023) is, according to Canon, the lightest f/2.8 zoom that reaches 300 mm. At about 2.6 kg it is slightly lighter than the 400.

In return the prime offers more reach: 400 mm against 300 mm, and up to 800 mm against 600 mm with the 2x extender. The zoom covers everything from 100 mm.

Which one suits whom?

• RF 100-300: You shoot sports or events at varying distances and want to zoom flexibly at f/2.8.
• RF 400: You have fixed positions, for example in a stadium or for wildlife, and need the reach without an extender.