Expect more original installations, with the country's largest light festival back for another year.

Tens of thousands are expected at the fifth Art in the Dark at Ponsonby's Western Park over the next four nights.

Founder Celia Harrison says volunteers have been hard at work making sure this year's event has a few surprises.

"We've got about 100 people involved in setting up, rain or shine, and there's a really incredible energy going out throughout the park."