https://visualeducation.com/class/photoshop-demonstration-colour-techniques-2/

Colour is an important part of photography, so knowing how to control and manipulate it in the post-production stages is a useful skill to have.  This live session, which builds on our Fundamentals of Post-Production and Live Photoshop Demonstration shows, goes into great detail about colour, how we can adjust, but also why and when we may want to adjust colour.  Throughout the show, Karl discusses four distinct points: Reasons to change colour; the importance of selections and masks when changing colour; colour reality; and ways to change colour.