其實在底片機時代就有了 或許現在還找的到 Sigma 28-80 3.5-5.6 HF LENS This new generation of compact standard zoom lens retains the same 1:2 (Half Lifesize) Tele-macro capabilities of its predecessor. However, it incorporates a Helical Focusing system for convenient use of polarizing or graduated filters. This also allows a "Perfect Hood" (supplied) to be used. This lens also utilizes a new optical design, and a "flare-cut" aperture, providing even better optical performance. And a convenient "Depth Scale" is displayed on the lens barrel to help calculate Depth-of-Field. This is the most desirable lens in the 28-80mm category.
Weight: 255 g Length: 7.1 cm Lens System: Zoom lens Optical Zoom: 2.9 x Min Focus Range: 50 cm Lens Aperture: F/3.5-5.6 Focus Adjustment: Automatic, manual Focal Length: 28 mm - 80 mm Lens Construction: 7 group(s) / 7 element(s) Filter Size: 55 mm Special Functions: Zoom