Autofocus lens for macro photography up to life-size (1x) magnification. Inner focusing affords a long working distance of 5.9in. (149mm) at 1x. A 3-group floating system results in excellent delineation at all focusing distances.

The 100mm f/2.8 macro lens will focus over the full range from infinity down to life size (1:1 reproduction ratio). This lens will impress any serious photographer with its combination of versatility, image quality and superb handling. A high-performance ring type Ultrasonic Motor provides fast and silent AF throughout its focus range, and even more significantly, allows full-time manual focusing permitting the close-up or macro shooter to instantly override the AF whenever necessary.

• Advanced optical formula with a three-group floating element system for exceptional close-up performance
• Internal focusing means the lens length is constant
• Secondary diaphragm to block stray light at f/2.8 & increase contrast when shooting in backlit conditions
• Ultrasonic Motor provides outstanding AF speed at all focusing distances
• Wide manual focusing ring with smooth action & fulltime manual focus override (even in AF mode)

Read more at Canon USA

Reviews

Canon EF 100mm f/2.8 Macro USM vs Tamron SP Autofocus 90mm f/2.8 DI Macro Lens by photo.net

This exercise has surprised me somewhat in that I knew the Tamron lens was considered pretty good, but I did expect the Canon model to be significantly better. In this test at least, this hasn’t proven to be the case. Both lenses display excellent sharpness and contrast, and the only significant advantage the Canon has is in it’s vastly superior flare control. Other differences are fairly minor: the Canon lens has better saturation, more working distance and better AF – it is clearly a superior product – but the Tamron does very well to come so close (and to even surpass the Canon lens at high magnification) especially when you consider that it is up against one of Canon’s very best.

Canon EF 100mm f/2.8 USM Macro Lens Review by the-digital-picture.com

The Canon EF 100mm f/2.8 USM Macro Lens is an excellent macro lens – and may be Canon’s most fun per dollar lens. This is the lens I most frequently recommend for someone starting out in macro photography.

The Canon EF 100mm f/2.8 USM Macro Lens is a medium-small lens and is rather light in weight. This is a very comfortable-to-carry-and-use lens. Build quality is decent but not as solid as Canon’s L Series lenses.

Canon EF 100mm f/2.8 USM macro – Review / Test Report by photozone.de

The Canon EF 100mm f/2.8 USM macro was introduced back in march 2000 replacing the old EF 100mm f/2.8 macro (featuring a classic micro motor). On APS-C DSLRs the field-of-view resembles a 160mm full format equivalent. The primary application of the lens is, obviously, macro photography but it’s not limited to that – infinity focus is possible.