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【新訊】Canon 兩顆 RF-Mount 新鏡報到!RF 85mm f/1.2L USM DS 與 RF 70-200mm f/2.8L IS USM!

Canon 這是要逼死誰.......

不過,終於可以帶70-200出門了....
diffusionless wrote:
前面網友就是問明明結構都一樣,為何MTF不一樣,而且請記住這個是一顆F1.2光圈的鏡頭,他的球差可不是F2.8或F2可以相提並論。

这个佳能官方刚发布DS镜头的时候就说了,靠的是镀膜改变

https://www.usa.canon.com/internet/portal/us/home/learn/education/topics/article/2019/may/Two-Powerful-Canon-Portrait-Lenses-RF-85mm-F12-L-USM-vs-the-RF-86mm-F12-L-USM-DS/Two-Powerful-Canon-Portrait-Lenses-RF-85mm-F12-L-USM-vs-the-RF-86mm-F12-L-USM-DS

Defocus Smoothing is a coating technology, similar in some ways to the general concept of apodization technology, which has been a part of optical design in the lens industry for some time. In the case of the RF 85mm F1.2 L DS lens, a special optical coating is added to two lens elements, which progressively smooths the edges of out-of-focus areas (compared to the RF 85mm F1.2 L without DS technology). Simply stated, the DS lens gives even smoother “bokeh” and rendering of out-of-focus highlights, particularly when it’s used at or near its maximum f/1.2 aperture. The edges of out-of-focus highlights with the DS lens, in particular, are smoother — this is the biggest difference between these two 85mm f/1.2 lenses.

Because DS coating is indeed a coating technology, it does not rely on added optical elements or “soft focus” optics to achieve its results. Accordingly, the DS lens’ size and weight are essentially the same as with the RF 85mm F1.2 L USM lens, along with its outer appearance, and basic optical performance. The DS lens uses the same general optical design as the conventional RF 85mm F1.2 L; the major distinction are the Defocus Smoothing coatings used on two lens elements.

球差还是那个非DS版本镜头的球差,镀膜相当于塞了个渐变滤镜

与stf的区别是stf可以做成双叶片设计切换stf效果(sony的e口stf没有保留这个设计,比较可惜),并且stf还做大了像场保证边角光斑。
CANON見證偉大的實力出來了,才一年多強大的鏡頭群已經成形,接下來應該會有小三鏡頭群的出現吧!
QQJOSEQQ wrote:
CANON見證偉大的...
接下來應該會有小三鏡頭群的出現...(恕刪)

隔壁棟表示極為害怕,
最近早被 RF24-105L
現已將原本自傲的 42K 售價降價成 38K
以期滿倉庫貨可以不要擺到發霉!
若您發現偶無回應就是我去山上拍照囉!
jjx874 wrote:

这个佳能官方刚发布...(恕刪)

按這個原廠說明,鏡片設計是不變,並不能代表球差不變,球差基本問題就是在於中央邊緣有路徑差,對於一般鏡片中央至邊緣的光線是相近,在經過DS鍍膜後中央至邊緣光線就降低,那原本球差就會下降。
這樣也類似縮光圈後,產生影像解析上升的情況,目前以上理解才能解釋mtf不同。


吉姆林 wrote:
Canon 今日除了...(恕刪)

太好了 這下有便宜的 RF 85可以撿囉
QQJOSEQQ wrote:
CANON見證偉大的實力出來了,才一年多強大的鏡頭群已經成形,接下來應該會有小三鏡頭群的出現吧!...(恕刪)

短短一年推出十顆鏡頭(EFS十幾年時間也才多沒幾顆),而且還有很多創新跟突破,不是重覆人家的舊路
很期待接下來一年會不會也推出十顆鏡頭?超高畫素應該會接著推出吧
我的理解不知道有沒有錯?這種DS鏡頭散景固然迷人,但是一樣的最大光圈F1.2,T值卻會比一般版差一點,所以用在弱光拍攝的,一般版更好。
diffusionless wrote:
按這個原廠說明,鏡片...(恕刪)

球差是不变的,这种镜头首先就得校正球差到几乎完美的状态,就是光线经过镜组全部汇集在中心点,不是你那幅图,那个是球差未矫正的状态。

因为一开始就设计成了球差几乎完全矫正的状态,所以加不加镀膜不会影响焦点位置
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