Sigma 18-200mm f/3.5-6.3 DC Lens for Pentax and Samsung Digital SLR Cameras from Digital Camera Showroom

This high zoom ratio lens is exclusively designed for digital SLR cameras and capable of covering a wide range of focal lengths from wide-angle to telephoto. Two Special Low Dispersion (SLD) glass elements and two hybrid aspherical lenses offer the utmost correction for all types of aberrations, and enables this extended range super zoom lens to be housed in a compact and lightweight construction of 70mm (2.8") diameter, and 78.1mm (3.1") in length, and weighing just 405g/14.3oz. The new lens coating reduces flare and ghost, which is a common problem of digital cameras and also creates an optimum color balance. This lens has a minimum focusing distance of 45cm (17.7") at all focal lengths and has maximum magnification of 1:4.4.The lens design incorporates an inner focusing system, which prevents the front of the lens from rotating, making it particularly suitable for using circular polarizing filters and petal shaped lens hoods. The overall length of the lens does not change during focusing, ensuring convenient handling and ease of use. A zoom lock switch eliminates 'zoom creep' during transportation, a convenient addition when traveling.

Sigma 18-200mm f/3.5-6.3 DC Lens for Pentax ...- User Rating:
Summary for Sigma 18-200mm f/3.5-6.3 DC Lens for Pentax ...- Garbage - wait for Pentax
Notes on Sigma 18-200mm f/3.5-6.3 DC Lens for Pentax ...- This is the worst camera lens I've ever had the misfortune to use.

I wanted something I could travel with to replace my 18-55mm kit lens (I have a K100D) plus the 50-200mm telephoto zoom. These are great lenses but I was trying to hold down the bulk and weight, so I gave Sigma a try.

Big mistake. This thing is TERRIBLE. Horrible chromatic distortion -- I frequently got BOTH purple and green fringing effects on opposite sides. Depending on the zoom and the angle I was shooting at, I got laughably distorted barrel and pincushioning -- sometimes in THE SAME SHOT. Literally, the extreme barrel distortion would flare back out at the corners. And it won't focus properly -- the center will be fairly crisp but the edges will be completely gone -- not the far edges either, but a mere third of the way across the frame. It vignettes really badly.

This is a CRAPPY, CRAPPY lens. I've seen better on dollar trashcams in the thrift store.

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