As comments have pointed out the last ball changes colour ![Tongue :P](http://www.tekforums.net/Smileys/teksmileys/tongue.gif)
Ball looks whiter early on in the throw because of the light, its really the yellow one thats in the cup at the end.
TBH though it would have been better if he stuck to one colour ball(s)
If you have enough time and inclination its possible to do all of those, you just need the time and stupidity to bother.