Well...think I have this solved.  I did try a few different sensors and this Optek seems to be pretty good, although I did get some other samples in but they were very expensive...sampled just to play with them for a future project.
   
  OK, so I right shifted the ADC so the values I am seeing in the dark portion are generally setting the upper to MSB's ('3') while in the lighter area, its always lower....a delta value of about 500 (in decimal).  Given this, I created a dead band area, where I allowed the 'dark' value to range down to the upper or high value of the dead band, so that in the event the dark didn't set the upper two MSB bits, it wouldn't trigger a light area, and if the value read was in the dead band area, I essentially ignored it.  This is because as you transition from dark to light, and you sample in that area, you will see the voltage ramp up and down.  So this dead band essentially acts as a digital filtering.  Then if the voltage drops below the lower threshold of this deadband area, it is a light area.  So the transistion is now more of a hard change rather than trying to detect where in the slope you are.
   
  So far with my testing, I'm right on and no longer have these false transistions.
   
  Sometimes....the easy things....are just hard  :-)

       
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