https://www.creativelive.com/class/color-matching-photoshop-jason-hoppe

Stop depending on Photoshop's Match Color feature, and learn how to match any image color, no matter the use case. Learn how to use the hidden features of the eye dropper tool. Use the info panel to fully understand color composition. Apply color adjustments with an eye for preserving the highlights and shadows of the original image, while expertly importing the sample color to your image.