摘要
屏幕软打样是建立在色彩管理基础之上的,色彩管理中颜色匹配的准确性直接决定了最终的屏幕软打样效果。本论文对屏幕软打样的色彩管理过程进行了研究和分析,对显示器和印刷机进行了设备特性化,在Photoshop软件中实现了屏幕软打样,并使用Profile Editor软件的特性文件编辑功能对屏幕软打样的颜色匹配效果进行了优化,最后对优化后的屏幕软打样效果进行了客观测试和主观评价。
研究结果表明,对EIZO显示器进行特性化时,将色温设置为5000K,伽玛值设置为1.8,亮度设置为100cd/m2时,显示器显示的颜色具有较好的准确性、稳定性和均匀性。在Photoshop软件中进行屏幕软打样的色彩管理设置时,从图像源设备色空间转换到印刷色空间时,应选择感觉目的再现意图,从印刷色空间转换到显示器色空间时选择带有黑点补偿的相对色度法,这样获得的打样视觉效果最好。在通过编辑特性文件进行屏幕软打样颜色匹配效果优化时,首先进行整体亮度和对比度调整,再进行灰平衡调整,然后进行阶调层次调整,接下来进行整体饱和度调整,最后进行选择性校色的方法,能产生较好的颜色匹配效果。屏幕软打样颜色匹配效果优化后,客观测试平均色差降低到3.81,主观评价结果介于相似和可接受两个等级之间,评价结果表明,优化后的屏幕软打样效果有明显改善,软打样可以应用于实际的印刷生产。
Soft proofing is based on color management and the effect of soft proofing is determined directly by the accuracy of color match in color management. This paper is aim to investigate and analyze color management process in soft proofing. The monitor and printer are characterized, the soft proofing is executed in Photoshop, the effect of color match in soft proofing is optimized used the software of Profile Editor, and the results after optimized are tested by objective and subjective evaluation.
The research results show that, the accuracy, stability and uniformity of the color displaying on monitor will be good when the color temperature is set to 5000K, the gamma is set to 1.8, and the brightness is set to 100cd/m2, during the character process of monitor. When executing color management setting for soft proofing in Photoshop, perceptual rendering intent is selected to process the color transforming between image resource device and printer color space, and relative colorimetric is selected to process the color transforming between printer and monitor color space. In order to improve the effect of color match by editing the profile of printer, the different functions of Profile Editor must be used in sequence, first for brightness and contrast adjustment, secondly for gray balance, thirdly for gradation, fourthly for saturation, and last for selective color adjustment. After optimized, the mean color difference has reduced to 3.81, and the subjective evaluation result is found between "similar" and "acceptable". All these results show that the effect of soft proofing has been improved widely, and soft proofing can be used in practice.
引文
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