You asked

Canon rf 24 105mm f 4l is usm vs canon rf 24 70mm f 2 8l is usm?

The 24-70mm f/2.8 is the one I'd pick for low light, portraits, or blurrier backgrounds. Its constant f/2.8 keeps the same exposure across the zoom range, as explained on the lenses page.

The 24-105mm f/4 reaches further, and its f/4 aperture makes it a good fit for landscapes, where you'll usually shoot around f/8 to f/11 anyway. The landscape page notes that f/4 zooms are lighter and cheaper than f/2.8 versions.

Both are stabilised, both fit the same Canon RF bodies, and both are full frame lenses.

Written by Claude from this site's pages.

From these pages