色彩管理对设计师、摄像师和艺术家非常重要。
Richard Hughes
richard@hughsie.com
TeliuTe
teliute@163.com 2011, 2012

# 色彩管理为何非常重要？

色彩管理是使用输入设备捕获颜色、在屏幕上显示颜色，然后全部打印，同时在每个介质上维持准确的颜色和颜色范围的过程。

冬季霜冻天气里的一只鸟的照片也许能够很好地说明色彩管理的必要性。

相机取景器中看到的站在结满冰霜的墙壁上的鸟

典型地显示出蓝色通道过饱和，使图像看起来很冷。

这是用户在典型的商务笔记本电脑屏幕上看到的画面

Notice how the white is not “paper white” and the black of the eye is now a muddy brown.

这是在用一般喷墨打印机打印后用户看到的画面

这里的基本问题是每台设备能够处理不同的颜色范围。因此，虽然您可能能够拍摄一张烤蓝金属色的照片，但大多数打印机却无法将其重现出来。

Most image devices capture in RGB (Red, Green, Blue) and have to convert to CMYK (Cyan, Magenta, Yellow, and Black) to print. Another problem is that you can’t have white ink, and so the whiteness can only be as good as the paper color.

Another problem is units. Without specifying the scale on which a color is measured, we don’t know if 100% red is near infrared or just the deepest red ink in the printer. What is 50% red on one display is probably something like 62% on another display. It’s like telling a person that you’ve just driven 7 units of distance, without the unit you don’t know if that’s 7 kilometers or 7 meters.

In color, we refer to the units as gamut. Gamut is essentially the range of colors that can be reproduced. A device like a DSLR camera might have a very large gamut, being able to capture all the colors in a sunset, but a projector has a very small gamut and all the colors are going to look “washed out”.

In some cases we can correct the device output by altering the data we send to it, but in other cases where that’s not possible (you can’t print electric blue) we need to show the user what the result is going to look like.

For photographs it makes sense to use the full tonal range of a color device, to be able to make smooth changes in color. For other graphics, you might want to match the color exactly, which is important if you’re trying to print a custom mug with the Red Hat logo that has to be the exact Red Hat Red.