Abstract: In various embodiments, methods are provided for detecting surface defects in in the preparation of a surface for overcoating (e.g., in a painting operation) where the method comprises applying to a surface being prepared for overcoating a highlighting liquid composition that increases the gloss of the surface onto which is applied, wherein said highlighting liquid substantially comprises odorless mineral spirits; examining the glossy surface for surface shape irregularities; and removing any noted surface shape irregularities by mechanical means.