減震系統效果如何?
尼康宣稱減震系統讓攝影者相當於使用三級以上的快門(八倍的快門速度) 或是說讓攝影者相當手持八倍長的時間 但是實際應用上結果如何呢?Nikon claim that their VR system is capable of reducing camera shake to a level where it offers the equivalent of shooting with a shutter speed three stops (8x faster) faster - but what exactly does this mean in practice? 尼康並不是宣稱減震系統可以完全消除相機的抖動 他們說的是: 假設在1/125秒快門時 影像有25%的機會會因震動而模糊 那麼開動減震系統後 平均而言 同樣焦距鏡頭在1/15秒 震動模糊的機率可以維持在25% 同理 一般說手持400mm的鏡頭要用快於1/400秒才能保持畫面清楚 並不表示開了減震系統就可以放心的手持八倍快門到1/50秒! 造成像機抖動畫面模糊的因素很多 甚至攝影者的呼吸心跳和風速都可能影響相機在快門打開瞬間的穩定性 所以減震系統的功效要視實際狀況而定 VR鏡系必須在支援VR系統的像機上才能開啟減震功能 在其他機身上就沒有減震的功能 (原文出版時Nikon F6, F5, F100, F80, F75, F65, D2-series, D1-series, D100, D70, and D50可支援VR) 客觀說來 在只能手持相機而快門速度偏長的狀況下 減震系統是個很有用的功能 但是它絕對不能取代一個牢固的腳架加上純熟穩健的攝影技術 Well it is not the same as saying that VR eliminates all risk of camera shake or vibration from ruining a shot! What Nikon is saying is if there is a 25% risk of camera shake occurring at 1/125 second with a particular focal length lens, then on average, with the VR activated the risk remains the same if that lens is used at 1/15 second. Nor does it mean if you apply the often-quoted rule of thumb that states the slowest shutter speed for any particular focal length for hand-held shooting should be its reciprocal that VR will be effective at a shutter speed three stops slower. For example, using a focal length of 400mm, the rule of thumb suggests a minimum shutter speed of 1/400 second would be required to achieve a sharp image with a hand-held lens, but there is absolutely no guarantee that with VR active shooting at 1/50 second (equivalent to three stops slower) will produce usable results. Many factors affect the ability of photographers to hand hold a camera and achieve acceptably sharp images including their physiological condition (e.g. respiration rate due to their level of exertion), shooting conditions (e.g. atmospheric influences such as high winds) and the actual length of the exposure. Therefore, use of VR should be considered on a circumstance-by-circumstance basis. If you want to use a VR lens it is imperative you consider the model of camera you will use as well, since only certain Nikon cameras support the VR system. Currently, the Nikon F6, F5, F100, F80, F75, F65, D2-series, D1-series, D100, D70, and D50 are the only Nikon camera models that are compatible with the VR feature; VR lenses can be used on other Nikon cameras but VR will not function. To put Nikon's VR system into perspective it is an extremely useful feature that helps to achieve sharp pictures in those situations when there is no alternative to shooting with a camera supported by hand but it is no substitute for a solid camera support such as a tripod, and a well-disciplined camera technique
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