The stracci tinti method was innovated in the Dutch Republic between 1650 and 1750, making Dutch blue paper a coveted commodity for artists including Venetian pastelist Rosalba Carriera (1673/75 ...

In Procreate and other apps, different elements of your drawing can be stacked on top of one another. So, for example, you can work on the background of your picture without altering the foreground.