Digital BW, The Print

Greetings,

With the driver I am using on the UC 7600, in the Print dialogu box, under Printer 
Features, Basic Settings, Ink Type, I have choices, two of which are "Seven Color Photo" and 
"Five Color Composite".  What's the difference between the two?  Clearly Seven Color Photo 
accesses all seven inks.  Which inks does Five Color Composite access?  What's the 
difference between a "Photo Composit" Ink Type selection and a purely "Photo" selection?

Thanks in advance,

Nathan Jones