Designed to deliver ultra-high quality images along with lightning fast operation, the new Canon EF 70-300 f/4-5.6L IS USM telephoto zoom lens brings a favorite zoom range to the celebrated Canon L-series of lenses. It features two Ultra Low Dispersion (UD) elements for improved image quality and reduced chromatic aberration, incorporates a floating focusing mechanism for sharpness from close up to infinity, plus an IS system that increases usability by approximately four stops. The EF 70-300 f/4-5.6L IS USM features a function that prevents erroneous operation when the lens is mounted on a tripod or monopod. Gleaming white, with a removable tripod collar, dust and water resistant construction, and a newly developed Fluorine coating that keeps soiling, smears and fingerprints to a minimum, its phenomenal performance and flexibility is assured. For portraiture or to bring what's far away up close, this addition to the L-series is guaranteed to perform.
Strengths: Compact, Light weight, Fast auto focus (with both full and panning modes), Full time manual focus, Very sharp images, Responds well to micro focus adjustment
Weaknesses: Cost, but then again it has 'L' build quality and performance; Lens collar is both expensive and (currently) unavailable.
Bottom Line:
Purchased 70-300L for use on my 7D for daylight field sports, and most importantly, to carry while when traveling. Processed (in Lightroom & NIK Suite) images from the 7D + 70-300L compare very favorably with those from my 5D MkII + 70-200L MkII. For travel a 7D + 16-35L MkII + 70-300L gives you a compact, lightweight, one body, two lens kit that covers an effective focal range of 26mm to 480mm. Add a 5D MkII body, and your range now goes from 16mm to 480mm with only two bodies and two lenses! For serious landscape and portrait work, the 5D mkII + 70-200L MkII are (probably) the best there is; but for daylight sports, and travel, the 7D + 70-300L is definitely the way to go.