Image processing, highlighting hidden details

[Rafal]

This is indeed self-made, based on some standard tools I created and one dedicated mapping routine.

Then I would have yet another question.

The technique definitely looks "cool" and seems to indicate places where the scribe changed the pen or made a break and continued the work several hours later.
But does it really? It it possible that algorithm "exaggerates" small, random differences in hue and shows that something important happened at some place where in fact nothing important happened?

Actually I have little experience with writing with the goose feather  When you do it, you put the feather from time to time into ink, right? Does this method detects such moments and colour changes when the scribe put the quill into the ink?