Batman Beyond - How many episodes were done with actual cels?

[Golden Age Flash]

A friend of mine is collecting animation cels from Batman Beyond and wanted to know how many episodes were done with traditional animation. We've heard only 6, but she actually owns cels from about 8 different shows. Does anyone know when they made the jump to computer vs cel?
(seems like it was sometime during the second season)

thanx!

[James Harvey]

The first 26 episodes were done via traditional animaiton. Episode #27 kicked in the computer coloring. The first computer colored episodes? Eyewitness? The last tradionally colored episode? Terry's Friend Dates A Robot.