SIGMA 70-200 F2.8 EX OS IN EXCELLENT COND SELLING TO PURCHASE THE CANON 70-200 F2.8 VER 2. THIS IS A GREAT LENS AND PHOTOS ARE SHARP ASKING 1000.00..........

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　　The 70-200mm F2.8 EX DG Macro HSM II is one of Sigma's latest lenses, which was first announced in December 2007 for Canon, Nikon and Sigma, with a multitude of follow-on releases including compatibility for the staying SLR mounts (i.e. Four Thirds, Sony and Pentax; nevertheless none of these versions are yet shipping). It's a successor to the 70-200mm F2.8 EX DG Macro HSM of February 2006, with a refined optical design offering improved optical performance, and ends up being the 4th version of the same standard EX design first revealed in 1999 (which was itself preceded by a well-respected 70-210mm F2.8 for 35mm). The HyperSonic Motor (HSM) focusing system guarantees quick, silent and precise autofocus for users of all brands of DSLR, although Pentax users ought to understand that this lens is effectively of 'KAF-3' mount spec, and for that reason won't concentrate on bodies which do not support SDM lenses. Aside from that particular incompatibility, this is a design which will deal with nearly every DSLR ever made, and is for that reason of unusually broad purchaser appeal.

　　Sigma are fond of using a variety of letters in their lens names (most likely on the principle that when faced with a choice, prospective buyers will certainly purchase the one with the most initials) and the 70-200mm declares its credentials accordingly. 'EX' represents 'Excellence' and designates Sigma's premium lens line, with remarkable construct and optical quality, while 'DG' means that the lens finishes are optimized for use on digital SLRs, and the image circle covers the full-frame 35mm format. 'Macro' is a tip to the closer-than-usual minimum concentrating distance of just 1m, which compares positively to the 1.5 m more common of lenses of this course, although it has just recently been trumped by the 0.95 m of Tamron's SP AF 70-200mm F2.8 Di LD (IF) Macro.

　　Obviously as one of Sigma's flagship lenses, the 70-200mm F2.8 boasts an appropriately complex optical design, showcasing 18 aspects in 15 groups, two of which are Extraordinary Low Dispersion (ELD) glass and 2 Special Low Dispersion (SLD) glass for correction of chromatic aberrations. Other attractions consist of internal concentrating and zooming systems, and a quick-release tripod mount collar which can be gotten rid of from the lens in seconds. On paper at least, this is a lens which might interest a huge variety of photographers throughout a variety of abilities; so is it worthy of that interest?