投影機對比值的迷思

nchnmaf

對於對比的解說的好清楚呀,跟一般的認知真的是不太一樣。

glamor13

看了您新發表的亮度方面文章而尋到此篇，好專業，受益匪淺，

kh2209

Barco ANSI對比度和HDR在電影中的重要性

https://www.cinionic.com/news/cinema-projector-ANSI-contrast-whitepaper

白皮書原文下載

https://drive.google.com/file/d/1TRJ1czBmYcxJ7BRWyVLsXIKBpFJAwrq7/view?usp=drivesdk

節錄

This confirms that the sequential contrast is not a very representative way to assess perceived contrast.

As mentioned above, a projector’s ANSI contrast spec can be more representative of the actual  perceived contrast, since it comes closest to how the system will be used in reality. A projector  with a good sequential contrast can look very bad in an average room. A projector with a good  ANSI contrast will keep its image quality in most setups; although it is important to remember  that a badly designed room (high ambient light, many reflections,…) will ruin any experience.

projectors exceeding 5000:1; these numbers are a factor 5-10 lower for ANSI contrast. A projector with an ANSI contrast of 1000:1 is an exceptionally good projector.It is also important to understand that the impact of the internal projector technology also causes  a decorrelation between sequential and ANSI contrast. A projector with a high sequential contrast  can have a very low ANSI contrast, due to the technological choices in the projector architecture.

A projector with a mainstream sequential contrast can outperform a premium model when  comparing the ANSI contrast. This can be seen typically e.g. when comparing DLP-technology to  LCoS. The former holds its ANSI contrast better where for LCoS it has been measured to be a  factor 50 or more below the sequential contrast.

Conclusion  With the interest for HDR growing in cinema, so has the importance of a properly specified  contrast ratio. When evaluating and interpreting “the contrast ratio” of a cinema projector, it is  important to know that both sequential and ANSI contrast exist. The former is the easiest to measure (on site) and therefore the most frequently-used by manufacturers and integrators.
However, the ANSI contrast is a much more representative metric. It takes careful consideration  of the measurement conditions, but shows a better correlation with the perceived contrast by the movie-going audience. In its high contrast models, Barco has started including the ANSI contrast ratio as a specification.

翻譯:

這證實了順序對比不是評估感知對比度的非常有代表性的方式。

如上所述，投影機的ANSI對比度規格可以更能代表實際的感知對比度，因為它最接近系統在現實中的使用方式。具有良好連續對比度的投影儀在普通房間中看起來非常糟糕。具有良好ANSI對比度的投影儀將在大多數設置中保持其圖像質量;雖然重要的是要記住設計糟糕的房間（高環境光，許多反射......）會毀掉任何經驗。

投影儀超過5000：1;這些數字是ANSI對比度的5-10倍。 ANSI對比度為1000：1的投影機是一台非常好的投影機。了解內部投影機技術的影響也會導致順序和ANSI對比度之間的去相關，這一點也很重要。由於投影儀架構中的技術選擇，具有高順序對比度的投影儀可以具有非常低的ANSI對比度。

在比較ANSI對比度時，具有主流順序對比度的投影儀可以勝過高級模型。這通常可以例如看到，例如將DLP技術與LCoS進行比較時。前者保持其ANSI對比度更好，對於LCoS，它被測量為比序列對比度低50或更多的因子。

結論隨著人們對HDR在電影院中成長的興趣，正確指定對比度的重要性也是如此。在評估和解釋電影放映機的“對比度”時，重要的是要知道順序和ANSI對比度都存在。前者是最容易測量的（現場），因此是製造商和集成商最常用的。
但是，ANSI對比度是一個更具代表性的指標。它需要仔細考慮測量條件，但與電影觀眾的感知對比度有更好的相關性。在高對比度模型中，巴可已開始將ANSI對比度作為規格。

#以上為Barco論點及個人喜好
#為免斷章取義已上傳原文
#Barco已開始將ANSI對比度作為投影機重要規格
#翻譯是用咕狗翻譯語義自行解讀

kh2209

現實使用中，我們才能真正體會，對投射效果起到決定性作用的還是外界光的強弱。投影機ANSI對比與亮度越高，受到環境光的影響越小，是克服環境光最有力的武器，但還是建議正在使用各種家用投影機的朋友，儘量在一個較為昏暗的環境下觀看投影，這樣大家才能更好的體驗家用投影機所帶來的大畫面的感受。