Yury, I follow your work with great interest, but please allow me a small criticism today. In your writings, you often tend to use the term "drawing" where it should be "painting". This is driving me nuts, so I can't keep my smartass mouth shut anymore. Please understand, I don't wish to cause offense.
The difference is, drawing is done with lines and shapes (often dry and crisp) while painting is about color and form (most often wet and blended). Of course, they both overlap, and a drawing can be the precursor of a painting (e.g. pencil sketch). Once you have begun painting (after drawing) your work is a painting and no longer a drawing.
Wet media like watercolor and gouache would be used for painting, while ink most often turns into drawings. Conversely, dry media like pencil are mostly used for drawings, while pastels are pretty much paintings. If it's smeared or blended, it's probably a painting. So you can't "damage the parts of the picture that have already been drawn" because they were painted ;-)
I hope this doesn't confuse you too much. I love your work, drawn and painted.
Have a wonderful weekend - Folker
P.S. Your English is about 10,000 times better than my Russian. Спасибо, что выслушали.
RE: Little secrets of gouache."Northern Lights"