Personally, I think the greatest contribution of digital SLRs to the photography world is the revival of traditional manual lenses. In the digital age, it allows enthusiasts of old photography to experience the tactile sensation of old lenses again, while introducing the charm of these lenses to new photography enthusiasts. Before Sony mirrorless cameras entered the market, the Canon EOS 5D/5D2 was always the preferred choice for adapting traditional SLR lenses. I have personally adapted Contax/Yashica, Nikon, and M42 series lenses. The biggest challenge when adapting traditional manual lenses to digital SLRs is focusing. Apart from using a full matte focusing screen for naked-eye focusing, there are generally two options: (1) replacing the traditional split-image focusing screen to fully restore the traditional focusing method, and (2) adding a focusing chip to the lens adapter ring to restore autofocus (AF) focus confirmation functionality. These aids somewhat increase the convenience of manual focusing, but the precision ultimately depends on individual skill.
個人覺得Digital SLR對攝影界最大的貢獻,就是讓傳統手動鏡頭可以復活,在數位時代讓老攝影同好回溫老鏡手感,讓新攝影同好體驗老鏡魅力。在Sony無反相機上市前,Canon EOS 5D/5D2一直是轉接傳統單眼相機鏡頭的首選,我自己就轉接過Contax/Yashica、Nikon和M42系列鏡頭。傳統手動鏡頭轉接Digital SLR後,最大的挑戰是對焦,除了全磨砂裸眼對焦屏裸眼對焦外,一般還有兩種選擇 (1) 更換傳統裂像對焦頻,全部回復到傳統對焦方式,(2) 鏡頭轉接環加裝對焦晶片,回復AF對焦點確認功能,這些輔助多少增加了手動對焦便利性,精確度就看個人功力了。
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Left to right: Carl Zeiss Sonnar 2.8/135 T*,
Makro-Planar 2.8/60 T* C, Distagon 2.8/28 T*