A Revelation.

I never really understood the Zone System until I saw this example.  Two photographs.  One is of a Black Horse the other is a White Horse.  The light meter when reading the light reflected off of each horse will give an incorrect exposure for both horses.  Two different exposures will place the Horse in  Zone V in the middle of the Zone scale which makes them both Gray.  The Black Horse to be black needs to be "under exposed", the White Horse to be White needs to be "over exposed".  In Fred Pickers book he says, "Ansel Adams learned years ago how to manipulate this middle gray reading characteristic of reflected light meters to achieve predertermined print values.  He worked out a logical straightforward system that,...can be taught to a beginning photographer in an hour.  Teaching a photographer with more experience takes longer!"  This for me anyway was true.