This EF 100-400mm lens also provides numerous advanced functions and high performance features. Its newly designed optical system achieves the high picture quality expected of an L-Series lens while satisfying the strict conditions for a high magnifications zoom lens. Like the EF 300mm f/4L IS lens, this zoom lens also has two Image Stabilizing modes. Mode 1 is for use with normal camera shake and Mode 2 is when the lens is used for panning with moving subjects. Switches for the IS on-off plus Mode 1 and 2   The following are some of the advantages of the new EF 100-400mm zoom lens: Useable Handheld Shutter Speed Versatile in low-light conditions/situation where tripod cannot be used Ring Type USM with Full-time Manual Focusing (FTM) Extremely silent and high speed auto-focus and the FTM feature permits the use photographer to fine-tune the focusing even when the lens is in the AF mode Fluorite and Super UD Optical System Gives user high precision images and secondary chromatic aberrations (rainbow hues at the edges of images) are corrected Rear Focusing/Floating System Allows the zoom lens to have high image quality at all focal lengths "Zoom Touch" Adjustment Ring Permits free setting of zoom ring frictions The "Zoom Touch" adjustment ring, first appeared in the EF 35-350mm f/3.5-5.6 USM zoom lens, is to give the user a choice of a tighter or loose zooming action since both lenses are designed with the push/pull method as opposed to the twin-ring type found in all the other EF zooms. The zoom adjustment ring of the lens   << Back to Main . 1 . 2 . 3 . 4 . 5 .