The Mystery Continues

The last few drawings of mine have ended in small disasters.  After spraying the piece with a moderate coat of Krylon Workable Fixative (which I've been using for years), I've scratched my head and wondered if a gremlin had snuck in, grabbed a red pencil, and run amok on the picture:  an intense, reddish purple had appeared in multiple areas. Since this has occurred in skin tones and hair, I suspected one of the reddish browns was reacting with the fixative and bleeding.  Fixative is part solvent, after all. I slipped on my lab coat (figuratively) and decided to conduct an experiment with a before and after fixative scan. As it turns out, none of my suspects were guilty.  None bled as a result of the fixative.  But - I've always known that my colors darken as a result of applying fixative, so I thought it would be interesting to set the results side by side to see just how much.  The swatches are on Canson Wineless Mi-Teintes Touch paper (my new favorite color!), and the pencils are Prismas (because that's the main brand I use):

You can see all of the colors darken noticeably, with Nectar and English Red having the least change.  Some of the colors, like Pink, both darken and allow more of the paper color to show through.  Something to keep in mind when applying fixative.