Mariah Carey was forced to rough it with her co-stars while shooting new flick Precious, says the movie's director.

The singer's small role as a social worker in the forthcoming movie - which is currently receiving rave reviews at Cannes - has been receiving plenty of attention on account of the diva's dowdy makeunder for the part.

And according to director Lee Daniels, things remained equally unglamourous behind the scenes.

Daniels refused to give Mariah special treatment - and is sure the "deglamourising" experience was good for the 39-year-old.

He says: "Mariah had to share a trailer on set and was only allowed one bodyguard, not her usual entourage.

"It was hard for her to be deglamourised but I also think it was a growing experience for her."

Still, Mariah managed to get her own back by arriving fashionably late to the Cannes Film Festival party for the movie.

The star pulled out of an early evening appearance at the Nikki Beach party and didn't actually arrive at the bash until almost four hours after it started, according to reports.

Mariah's style