Why is there difference between the color displayed on colorimeter and the actual color?

From:Linshang Time:2021/11/10 15:49:54 Browse:40

LinshangTechnology currently has 7 colorimeters available,among which LS170, LS172, and LS172B are designed with 45°/0° optical geometric structure, widely used in the ink printing industry. LS171, LS173, and LS173B adopt D/8° optical geometric structure, suitable for general industries, especially for measuring objects with high gloss, etc.LS175 adopts large-caliber design, suitable for measuring objects with texture or rough surface. Linshang colorimeter have received high praise since its launch. At the same time, some customers are puzzled by a phenomenon that occurs when the colorimeter is measuring color:

Colorimeter screen and the actual color of the sample
The color displayed by the mobile and the actual color of the sample

1. Under different ambient light, the color seen by the naked eye will be different.

The national standard for color measurement "GBT 3978-2008 Standard Illumination and Geometric Conditions" defines two types of standard illuminators: A and D65. The D65 standard light source is used in Linshang colorimeters, which can ensure the consistency of the measurement conditions, not affected by ambient light during measurement. Beforethe appearance of the colorimeter, It needs to use a professional color matching light box to compare the color difference. The purpose of the color light box is to establish a standard lighting source to ensure that the human eye will not be affected by ambient light when judging the color difference. Normally, when observing objects with the naked eye, the ambient light cannot be consistent with the D65 light source of the colorimeter, so the color of the object seen by the human eye under ambient light and the color measured by the colorimeter will be different.

2. Due to the different ability to restore true colors, the colors of objects on different screens are different.

The screens of the five hand-held colorimeters on Linshang are all 3.5-inch IPS color capacitive touch screens. The two portable models need to be used with the mobile phone APP, but no matter which instrument, their display screens use RGB color space, which is not wide as the true color gamut. 

Colour Gamut Comparison
Colour Gamut Comparison

Therefore, when a color that does not belong to the RGB color gamut is measured, the instrument will automatically match the closest color in the set color gamut, which will cause the color and sample displayed on the screen of the instrument and the screen of the mobile phone connected to the instrument. The actual color is different. The difference between the two is that the phone screen has more color digits, and the ability to restore the true color of the sample will be better than the screen of the instrument. In addition, the color displayed on the mobile phone APP is inconsistent with the actual color of the sample because it is affected by factors such as the material, resolution, brightness, and filming of the display screen of the mobile phone. These factors cause the true color reproduction ability of the mobile phone screen to be different.

3. The different light irradiation angle and observation angle will also affect the human eye's observation effect on the color of the object.

Linshang colorimeters use two lighting methods: 45°/0° and D/8°. These two lighting methods simulate the different angles at which the human eye observes the object, so the observed color of the sample will also be different. Most of the colorimeters on the market do not display colors, but only indicate data. 

45°annular   illumination, 0° viewing angle

45°annular illumination, 0° viewing angle

D/8, Specular Component Include (SCI)

D/8, Specular Component Include (SCI)

The colors displayed by Linshang colorimeter are only for reference. In fact, the corresponding color space data displayed on the instrument shall prevail.