What are the common subjects of the paintings? Most palette knife paintings are portraits, or of people / animals. This is because palette knives produce clean but not very accurate marks on the page / canvas etc. The elaborate colours of the oil paints usually create a strong emotion; These emotions are not usually portrayed with an object such as a bowl of fruit. However, it is not impossible to have objects as the main subject of the painting - lots of successful artists paint objects like Shoes, teddy bears and other intimate objects. This - when done correctly - is just as successful.