In a boom and bust industry, a film expert says it's not unexpected to see Weta FX propose staff cuts

The Wellington based film and effects company confirmed changes to up to 100 roles, blaming sector challenges and project delays.

Weta's involved in large overseas productions like Avatar and King Kong.

Victoria University Film Professor Paul Wolffram says uncertainty in the US has lead to no money being put into film making, with large studios sitting empty.

He says things have been difficult for a few years with the current political situation in the US - and may remain uncertain for the next two or three years.