Quote Originally Posted by Michael R 1974 View Post
The key is to build up density slowly.
Agreed, or put another way - Thin the spotting ink to a point where it is at least two shades lighter than the area you are spotting. Carefully place the tiniest of spots in the center and allow it to dry. Have another look at the area in question and add another spot of ink and allow to dry. Repeat until the blemish is unnoticeable to the naked eye.