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Hands on: Light, compact, rugged, satin-finish polycarbonate barrel construction with plastic lensmount. Large, highly visible, white-on-black focal-length markings on more than amply wide, smooth-turning, easy-to-grip, rubberized-ribbed zoom ring. Smooth-surface, front focusing ringis a little awkward to grasp when recessed in infinity position, but does turn easily. Whisper quiet, smooth, ultrasonic focusing motor a pleasant surprise at this price. Front elements revolve during focusing so position-sensitive filters, such as polarizers and graduated filters must be attached after focusing. No aperture ring since apertures are set within camera body. Lens is eminently handholdable.
In the lab: SQF data was very good at 55mm and 135mm, and good at 200mm. Minimal pincushion distortion (0.20 percent) was seen at 55mm; noticeable pincushion (1.35 percent and 1.60 percent, respectively) was seen at 135mm and 200mm. Exposure at the film plane at both 55mm and 200mm was very accurate, with about 1/10-EV underexposure at every aperture, except 2/5-EV under at maximum apertures, due to light falloff, and about 1/4-EV under at minimum apertures.
At the closest 55mm focusing distance of 46 1/2 inches (1:16), center sharpness was excellent from f/4.5 to f/16, and very good at f/22. Corner sharpness was acceptable from f/4.5 to f/5.6, good at f/8, very good at f/11, excellent at f/16, and very good at f/22. Optimum performance was at f/16. At 135mm closest focusing distance of 47 1/2 inches (1:7), center sharpness was good from f/5.6 to f/11 and poor from f/16 to f/27. Corner sharpness was good at f/5.6, acceptable from f/8 to f/11, and poor from f/16 to f/27. Optimum performance was at f/5.6. At 200mm closest focusing distance of 47 inches (1:4.4), center sharpness was poor from f/5.6 to f/16 and acceptable from f/22 to f/27. Corner sharpness was poor from f/5.6 to f/11 and acceptable from f/16 to f/27. Optimum performance was at f/22.
In the field: Test slides were very sharp and contrasty at every focal length and aperture, except for center and corners at f/5.6 and and f/27 at 200mm, and f/5.6 at 135mm, where slight softness was noted. Light falloff was gone by f/11 at every focal length. Flare was very well controlled at all apertures and focal lengths.
Conclusion: A great bargain lens. Don't let the liberal use of plastic bother you, unless you're a pro planning on giving the lens one hell of a beating. Close-focusing capability at 135mm makes this a great portrait lens. Only defect: filter problems caused by revolving front ring during focusing.
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