Two Shades of Gray - 4/12/13

Someone (you know who you are!) sent me a puzzle recently that he had enjoyed.   I had an idea how it might work, but it turned out that idea was wrong.  I knew there had to be at least one puzzle out there that used the idea I had thought of, and it turned out I was able to find one without too much trouble.  The funny thing is, both the puzzle he sent me and the puzzle I found had exactly the same name.  So, today I offer you:

Shades of Gray from California and Shades of Gray from Pennsylvania.

Tomorrow we'll be in California to kick off a whole week of cipher puzzles.