Discovered a great tip for all D450 owners (PN/PS and size does not matter - only applicable to 450 though)
While digging around in the service menu, discovered that if you set the model number to PD550 you can now enable cinema smooth on 1080p/24 input
It really really does reduce judder, tested on wall-e, up and lord of the rings blurays.
The to picar films, wall-e and up used to judder badly, but now they are as smooth as silk
All other functions tested and working!
you will have to redo all your settigns for picture/sound when you exit from the service menu.