Andrew Loomis taught cool shadows outside and warm shadows inside. I have found this works well for me. I usually pick a prima donna color for my painting and mix a little of that color into every other color except it's direct compliment and use very little compliment. Some landscape artist will not use black but rather mix their darks from colors. I find that if you plan to have a print made using the 4 color process the print will look better and not looked washed out if your do use black. The print will only have yellow, magenta (fusha), cyan (turquoise) and black. Even the computer with its millions of colors must reduce itself to these four inks to be printed.
Can anyone give me advice or tips on painting shadows. I never know which colour to do these. I know they should be grey/black but should they also have some colour in? Getting the direction right is not so much a problem, just getting the shading right. Should it also graduate into the background or should there be a hard line. I'm talking about trying to get it as realistic as possible. Any help would be much appreciated. I'm tearing my hair out!