I need an extremely high resolution. My encoder has 8192 pulses per revolution, however I need to be able to see a 1 minute change in angular position. This means that i need 360*60=21600 pulses per revolution. Thus with a quadrature decoder I can get 8192*4=32768 pulses per rev. Believe me, after all of this trouble, I would much rather do without the decoder, as I feel more comfortable with the PIC by itself.