Conventional oil painting techniques often begin with the specialist illustrating the topic onto the fabric with grilling or thinned colour. Famous Paintings Oil colour is usually blended with linseed oil, specialist quality nutrient mood or other chemicals to make a slimmer, quicker or more slowly dehydrating colour. Landscape Oil Paintings Because these chemicals slim the oil in the colour, they can also be used to clean styling paint brushes. A primary concept of oil colour program is 'fat over lean'.