70's Horror Movie About Making a Horror Movie

by Kristin
(Flint, Michigan, USA)

Hi,

I saw this movie in the 70's. It's about a film crew that goes to a scary mansion to make a horror movie, but then it becomes a real horror movie as zombies rise from the dead.

It terrified me for years, so I'm not sure if I'm remembering it all correctly. I'd love to see it again through older eyes. Can anyone help with a title?