This tutorial goes over how to use the selective color tool inside Adobe Photoshop. Selective color is an amazing way to adjust colors in Photoshop while still maintaining a huge amount of control over what colors are effected by the changes.
Where changing the color of something via a method like hue / saturation will change every color in the image you're editing (assuming you haven't masked things out), selective color can target a specific color on the color spectrum and then you are presented with slider bars for all of the CMYK color options to really fine tune your image the way you want it to look.
Overall an awesome tool that I think is underused by designers as it is such a specialized tool, but it's definitely one worth knowing because it can be extremely powerful when trying to carefully tweak image and design colors.
Questions? Feel free to ask in the comments section! :D
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