Slutsats: 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.
Nackdelar: 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.
Slutsats: 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.
Nackdelar: 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
Summering: 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.
Fördelar: Highly versatile 11.1x zoom range, Great value, Relatively small and light - great travel lens, Polariser-friendly internal focusing
Nackdelar: Tamron version very similar, Pricier Nikkor version has anti-shake, Pricier Nikkor version is optically faster, Pricier Nikkor version has better build quality
Sigma AF 18-200mm f/3.5-6.3 DC - Review / Lab Test Report
18 maj 2006
Slutsats: There's no such thing as a free lunch in lens land and the Sigma AF 18-200mm f/3.5-6.3 DC is no exception here. The resolution figures are generally quite decent and regarding the extreme zoom range you may accept the very pronounced distortions present throughout the zoom range as well as a few other shortcomings. Unfortunately the AF accuracy leaves something to be desired with this lens especially towards the long end of the zoom range.
Sigma AF 18-200mm f/3.5-6.3 DC OS (Canon) - Review / Test Report
9 april 2006
Slutsats: The Sigma AF 18-200mm f/3.5-6.3 DC OS is an extremely versatile lens but performance-wise it is a bit of a mixed bag. The resolution characteristic varies significantly throughout its immense zoom range. Interestingly the extreme ends are actually the sweet spots of the lens whereas the 35mm setting is downright miserable at large apertures. The quality recovers at 50mm before dropping somewhat at 100mm again.