i think you could also do this with the echo effect.
try taking a layer and rotating it they way you want, then add the echo effect. increase the number of echoes and change the echo operator to ‘composite in back’ or ‘in front’ depending on your animation, and see if that can work for you.
you can also adjust the echo time (the default is the duration of a single frame at 29.97fps), and making that value positive or negative determine if the echoes trial the layer or precede the layer.
you’d still need to have a copy of that layer rotate and stop at the final point, so the echo layer would reveal that final layer.
Kevin Camp
Art Director
KCPQ, KZJO & KRCW