Ink washing is diluting your ink drawing by dragging a puddle of h2o over the site, just like watercolour portray techniques. The higher the focus of ink, the denser your shadowing. Inks like oxgall (made out of oak galls) and bistre (created from soot and wine) can be built https://elliotnsmco.blogkoo.com/5-simple-techniques-for-how-to-draw-with-ink-pens-54227445