Anamorphic lenses>to standard 35mm film.
Projection through anamorphic lenses from a standard 35mm film.
What anamorphic lenses does is to compress a wider field of view to a standard format so the more visual information can fit on a smaller aspect ratio.
Then in projection you need those lense to uncompress the image otherwise you will see what we have seen many times in TV sets the "Montiliani" figures.
What PD150/170 uses is a pseudo 16:9 which fits in the 4:3 aspect ratio thats why the maths doesn't fit.It's like a pseudo anamorphic.
720/576=1.25
1440/1080=1.33
1920/1080=1.77
See here.