tutsai wrote:
看了包裝內附的介紹,除了傳統紅圈的L鏡.現在又有了綠圈的DO鏡.
請問有人知道綠圈的DO鏡的特點在哪裡嗎?
Diffractive Optics
Diffractive Optics, a revolutionary new lens optical technology that permits super-telephoto lenses that are significantly shorter and lighter than previously possible, while simultaneously improving optical performance by reducing chromatic aberrations and even spherical aberrations.
http://www.usa.canon.com/eflenses/technology/diffractive.html
跟 APO 有點像,是用來將望遠鏡頭的色散效果消除,不過除了降低色散效果外,DO 的訴求是可以減少長度和重量。




























































































