The most important of Oil Painting "fat over lean" is one of the important concepts of oil paintings and one to follow to reduce the risk an oil painting splitting. 'Fat over lean' has got to do with the different dehydrating periods of oil pigments (which can vary from a few months to a fortnight) and ensuring that greater stages of color don't dry faster than decreased ones.Modern Paintings"Fat" oil color is oil color straight from the tube. Mixing it with an oil makes it even 'fatter' and enhances enough interval of time it needs to dry definitely (even though it may encounter dry to the get in touch with, it will still be dehydrating under the surface).