Conclusion: The 18-200mm F3.5-6.3 DC OS HSM is on the face of it an ideal 'do-it-all' travel lens; the 11x zoom range, image stabilization and useful close focus distance combine to give great operational flexibility. But of course this versatility comes at a cost, as optical compromises must necessarily be made to provide such a long range in a single lens.
Cons: Very inconsistent sharpness through the zoom range - extremely soft at 80mm, Soft corners at all focal lengths, Occasionally indecisive autofocus, Slightly less resistant to flare than its more recent competitors
Summary: Unsurprisingly a lens with this kind of focal range is rarely going to perform
as well as one with a shorter range, but we were impressed overall by the results
possible. Certainly unless you're into extreme wide or telephoto work, or demand
the ultimate quality, you could really be very happy with one of these lenses.
Pros: Highly versatile 11.1x zoom range, Great value, Relatively small and light - great travel lens, Polariser-friendly internal focusing
Cons: Tamron version very similar, Pricier Nikkor version has anti-shake, Pricier Nikkor version is optically faster, Pricier Nikkor version has better build quality
Sigma’s 18-200mm f/3.5-6.3 DC OS Lens; The First Multipurpose Sigma Zoom With A Built-In Image Stabilizer
1 December 2001
Excerpt: Although Sigma released their first lens with a built-in Optical Stabilizer (OS) system in the spring of 2004, the company employed this technology in only one pro-grade lens, the 80-400mm f/4.5-5.6. That has changed with the introduction of a more compact/affordable (digital-only) 18-200mm OS zoom.
Conclusion: After the announcement of the Sigma’s 18-200 mm OS suggested price my first impressions were rather negative – I didn’t think it could sell itself well. It turned out the Sigma company knew what they were doing – they simply appreciate the products they consider good. In this case they are perfectly right because the Sigma 18-200 mm ranks among very well-made optical constructions.
Cons: weak image quality at the frame edge for the range of 100-200 mm and near the maximum relative aperture,, distinct distortion level at 18 mm,, high vignetting for both extremes of the focal range,, high astigmatism for the range of 100-200 mm,, not very efficient image stabilization.
Excerpt: Ob Landschafts-Panorama, Porträt oder winziges Detail: Mit einem Zoom-Objektiv an Ihrer Spiegelreflexkamera sind Sie flexibel, ohne mehrere Objektive herumschleppen zu müssen. Das Sigma 18–200 F3.5–6.3 DC OS zeigte im Test von AUDIO VIDEO FOTO BILD gute Leistungen zu einem günstigen Preis.