On this video tutorial Aaron Nace from Phlearn talks color theory and how it can help you with your work in Photoshop.
The first part of this video deals with color theory – don’t be intimidated by the “theory” part – Nace actually talks about a very specific part – complementary colors. If you don’t know what are the complementary colors of reds for example you can use the very useful Adobe free website to find out (and by the way the answer is green or greens).
There are also triads of colors which you can find in the Adobe site as well – these are 3 colors that should go well together. On this video Nace shows how you can use a triad of colors to change an existing image and improve it’s colors. You don’t need to do this of course for each image but this will help you understand the basic idea of using complementary colors in your images.
The biggest tip for replacing color Nace brings to the table in this video is that once you pick a new color and put it on your selection in a new layer – you should use a blend color layer to make it more realistic (rather than just flat boring colors).