 This use of bright, contrasting colours as underpainting is not a common feature of frescoes, but it is commonly employed in both oil painting and tempera.Like Daniel, the Libyan Sibyl's yellow garment once had much more subtlety in its folds and shadows than it has now.There is absolutely no doubt that before the restoration, the whole ceiling was dirtier, more muted and more monochrome than Michelangelo ever intended, but when images of the frescoes are viewed in their stained and unrestored state the subtle washes and intense definitions, described by Beck and Arguimbau, still make their presence known, giving mass and bulk to the forms.