With increasing realism in painting, the halo came to be a problem for artists. In free-standing medieval sculpture, the halo was already shown as a flat disk above or behind the head. When perspective came to be considered essential, painters also changed the halo from an aura surrounding the head, always depicted as though seen full-on, to a flat golden disk or ring that appeared in perspective, floating above the heads of the saints, or vertically behind, sometimes transparent.
In in the early 15th century Jan van Eyck and Robert Campin largely abandoned their use, although other Early Netherlandish artists continued to use them. In Italy at around the same time, Pisanello used them if they did not clash with one of the enormous hats he liked to paint.