The Ghostmaker (2012) on Netflix

Plot summary

The college friends come upon an old coffin that dates to the 15th century. Inside it sits a contraption that is part clockwork and part supernatural, and it opens a channel to spirits. A living person who uses it can spend a period as a ghost, slipping past death while in that state. Their first trips into this mystery world are playful and innocent. The casket then begins to draw out the group's more dangerous impulses and darker desires, and the friends find themselves pulled toward evil.