What’s New. A new four-stop image-stabilization unit, optical design, and coatings make for solid improvements to picture quality.

Versatile and Functional. When used on a full-frame camera, the 24-105 II provides a constant-aperture, wide-to-short tele focal range that’s great for portrait and event photography. Using an APS-C sensor camera? You’ll have a focal length equivalent to 38-168mm. The constant f/4.0 aperture makes this lens an excellent choice for videographers.

Optical Refinement. The 24-105mm has seventeen elements in twelve groups with four aspherical elements. The Air Sphere Coating is applied to those elements to reduce flaring and ghosting. The ten-bladed iris provides pleasing bokeh, and could prove to be useful for video. The 24-105mm has a 1.48-foot minimum focusing distance.

Build Quality. The lens’s build has been refined with rubber seals to keep out the elements and dust. The front and rear elements have a fluorine coating to prevent smudges and make cleaning easy.