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The term superzoom or hyperzoom refers to photographic zoom lenses with unconventionally large focal length factors, typically more than 5×. The largest ratio for a digital SLR camera lens is held by the Tamron Di-II format (APS-C) 16–300 mm, giving 18.8×. Some bridge digital cameras have even larger zoom ratios more than 80x and the non-detachable lens compact cameras with same sensor size 1/2.3" as the bridge camera have superzoom up to 30×.〔(【引用サイトリンク】title=Nikon P900 vs Sony HX400 Comparison )〕〔(【引用サイトリンク】title=Best superzoom camera )〕 The Samsung Galaxy S4 zoom smartphone has optical zoom lens 10x with "zoom ring" and optical image stabilization,〔(【引用サイトリンク】title=Samsung officially announces Galaxy S4 zoom with 16MP camera, 10x optical zoom )〕 For movie and television use, Panavision holds the record with their 300X (7-2100mm, 23-7000mm 35mm equivalent) HD Lens with Compound Zoom Technology (two or more lenses mounted together).〔(Panavision 300x Zoom Lens ) Panavision (PDF)〕 While superzoom lenses have improved greatly in recent years, they still have a number of drawbacks in comparison with shorter-range zooms and prime lenses, chiefly their typically smaller maximum aperture. The longer the zoom lens, the greater the possibility of vignetting when using the wide and widest angles, especially if optical filter(s) are attached to the front of the lens. Even at the longest range, falloff (darkened corners) can be seen. The magnitude of vignetting and falloff depends on the apertures. Opening a smaller diaphragm will usually reduce vignetting and falloff, but as a consequence of loss of ample light and loss of broad/deep depth-of-field.〔(【引用サイトリンク】title=Nikon 18-300mm VR DX AF-S G ED NIKKOR )〕 == History and development == The first zoom for photo cameras was introduced by Voigtländer in 1959 (Voigtländer ZOOMAR 1:2,8/36–82 mm). It was in fact designed by an independent lensmaker Zommar from Long Island, New York. That same year Nikon introduced a Nikkor 85–250 mm/1:4.0-4.5 for the new Nikon F. The first zoom affordable for amateurs was the Vivitar series I 1:3.5/70–210 mm of 1973, with a breathtaking for its time focal length range. Other superzoom lenses included a 100–500 mm/1:8 Rokkor from Minolta and a 360-1200/1:11 Nikkor from 1976. In 1980 Tokina brought a wide-angle-to-zoom with the enormous focal length range of 1:4.0/28–85 mm to the market. Only two years later Tokina presented the first super zoom shot, for that time, which covered a focal length spectrum from 35–200 mm (1982). The focal length range was again increased in 1985, when Kiron presented the first zoom lens with a focal length range of 28–210 mm. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「superzoom」の詳細全文を読む スポンサード リンク
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