Let's test the color picker using the sensor.

Light colors are recognized as slightly greenish. This is probably because the white LED for reference is not completely white.
Also, the color readings change depending on the distance between the sensor and the object, as well as the surrounding brightness and lighting. In order to stabilize the readings, a cylindrical cover is attached to the sensor case to keep the distance between the sensor and the workpiece constant while shielding it from outside light.