|  Product Description
 
  
 The addition of the 18-250mm F3.5-6.3 DC Macro OS HSM speaks to Sigmas 
versatile product lineup with this multipurpose zoom lens that offers Optical 
Stabilization (OS) and covers wide angle to telephoto to macro photography. It 
differs from Sigmas current 18-250mm F3.5-6.3 DC OS HSM lens with its even more 
compact size, its macro capability with a maximum magnification ratio of 1:2.9 
and the use of Thermally Stable Composite (TSC) material currently used only by 
Sigma.
 TSC, which is incorporated into the lens barrel and is often compared to 
polycarbonate, has a high degree of elasticity and exhibits little variation in 
its structure in extreme temperature conditions. This means that internal barrel 
expansion and contraction due to extreme temperature variations is less 
prevalent. TSC also contributes to the lens size reduction. The non-macro 
18-250mm F3.5-6.3 without TSC weighs 22.2 ounces and is 3.1 by 4 inches in 
diameter, whereas the new macro lens is 16.6 ounces and 2.9 by 3.5 inches in 
diameter.
 
 Sigma optimized this lens power arrangement by incorporating double-sided 
aspherical lenses and reexamining the design to achieve a more compact filter 
diameter. The lens has an approximate 13x high zoom ratio with a filter size of 
62mm in diameter. Sigmas unique OS system, as well as one Special Low 
Dispersion (SLD) glass and three aspherical lens glasses, compensate for camera 
shake and enable correction of color aberration, respectively.
 
 The new 18-250mm F3.5-6.3 DC Macro OS HSM lens is also equipped with Super 
Multi-Layer Coating to reduce flare and ghosting, a Hyper Sonic Motor (HSM) to 
ensure fast and quiet auto-focusing, and a rounded, seven-blade diaphragm to 
create an attractive round blur to the out of focus areas. The lens features a 
brass-made bayonet mount applied on the surface to reinforce strength for 
long-term use and enable high accuracy and solidity.
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