不同环境条件下同一色标的数码色度值之间的相互关系

The interrelations of digital colorimetric values of the same shade tab obtained in different environments

目的研究同一色标在不同环境条件下拍摄的数码色度值之间的变化规律。方法先在暗房中拍摄Vita 16色比色板各色片并输入Abode Photoshop CS软件,采集各色片色度值制作成标准数据库,然后选择白天没有阳光直射的背光诊室和关闭普通窗帘的白天诊室,将A2色片与其他色片并排对称在一起拍摄,每张照片输入软件后调整其中A2色片的色度值到标准数据库中A2色片的色度值,检验并排拍摄的色片的色度值与标准数据库中同色号色片的色度值之间的色差。结果 16色比色板中各实验组色片经过软件调整有63.89%的色片色差值≤2,有82.78%的色片色差值≤4。结论只要数码相机性能稳定,设置保持不变,光源亮度足够,其所拍摄的色片数码色度值基本稳定,通过软件调整色差在肉眼不可察觉的有63.89%,色差在临床可接受的范围的达82.78%。

Objective To investigate the interrelations of digital colorimetric（CIE） values of the same shade tab obtained in different environments.Methods First,the image of each shade tab of Vita 16 color shade guide was taken by a digital camera in the dark room and entered Abode Photoshop CS software.The CIE values of all shade tabs were collected and form a standard database.Then,in the daytime,in the clinic without direct sunlight with curtain close,placed A2 shade tab and each other shade tab symmetrically in the line and took photographs.After inputting each photograph,the CIE value of A2 shade tab was modified to its corresponding value in standard database.The difference between CIE value of each other shade tab in the photo and their corresponding value in standard database was assessed.Results After modified by using software,of 16 shade tabs,63.89% of them whose color difference value was ≤ 2,and 82.78% of them whose color difference value was ≤ 4.Conclusion As long as the performance of camera is stable,setting keeps the same and light resource is bright enough,the CIE values of shade tabs can be stable.After modified by using software,color difference which could not perceived by naked eyes is 63.89%.Color difference which could be acceptable in clinical practice is 82.78%.