Excerpt: Pro shooters have been asking Canon for an image-stabilized, wide-angle, general-purpose zoom with a constant aperture, weather resistance, and full-frame coverage.
Excerpt: Canon EF 24-105mm f/4L IS USM was first announced in August of 2005, targeting event/street photographers who require a lens with moderate wide to medium telephoto
Canon EF 24-105mm f/4L IS USM, (tested with cropped-frame APS-C body)
Camera Labs
1 March 2008
Summary: There’s no denying the Canon EF 24-105mm is a high quality lens. It has decent optics, the excellent mechanical and build quality you’d expect from Canon’s L series,...
Pros: Canon 'L' build and mechanical quality., Effective IS and quick USM focusing., Polariser-friendly internal focusing., Compatible with full-frame bodies.
Cons: Lacking wide-angle on cropped bodies., Relatively expensive., Fringing visible even on cropped-frame., Less compelling if you're not going full-frame.
Excerpt: Gary Wolstenholme takes a close look at this popular 'L' series lens which covers a 4.4x zoom range, has a constant maximum aperture of f/4 as well as image stabilisation
Pros: Excellent resolution in the centre throughout the zoom range, Excellent performance towards the edges when stopped down, Great Image Stabiliser, Good build quality, Fa...
Cons: CA levels towards edges throughout the zoom range a little high
Excerpt: Boasting the superb build, mechanical and optical quality found in the Canon L-Series Lenses and a widely used range of focal lengths, the Canon EF 24-105mm f/4 L IS USM
Summary: The lens did however have a rocky start, with early models suffering from an internal flare problem , forcing returns and delaying wider distribution.
Pros: Useful wide to short telephoto range, Effective anti-shake IS capability, Fast and quiet USM focusing motor, Polariser-friendly internal focusing
Cons: Relatively expensive (at list price), Corners slightly soft at telephoto end, 24-70 f/2.8L has better build and focusing, 17-40mm f/4L an affordable alternative
Conclusion: The Canon EF 24-105mm f/4 USM L IS is surely one of the better standard zoom lenses for full format EOS DSLRs but it's not perfect within this scope nonetheless.