Homebrew PCBs

Hello All,

For years i have been making UV exposed PCB's without a problem.
Even SMD and traces of 10 mill go well.
But lately i have trouble printing my layouts on film. For years i
used Calque tracing paper as film. The last time i found that these
are not x/y stable.

The boards i made before where never this large or complex or had this
amount of pin-headers.

Could any recommend better film ?

grtz

Simon