Whoopi Goldberg initially turned down the lead role in hit movie The Color Purple because she didn't think she was worthy of the role of CELIE.

The humble actress was stunned when Steven Spielberg handed her the part because she simply wanted to be a member of the cast.

She says, "He gave me the part, I turned it down because I thought I should have a smaller part. I'd never made a movie before, I didn't know it takes months; I thought you went in and did it like a theatre piece."

But Goldberg ended up with an Oscar nomination for the part and admits she learned a lot about movie making on the set.

She explains, "At the end (of the film), where you see all those purple flowers, they were in buckets. That field was the cornfield, it was the poppy field. I would come in... I'd say, 'How did they do that..? Last night this wasn't here.'

"The clay, they brought it in and put it on the ground, just rolled it out; we walked on it like we were in Georgia. It was the most amazing thing. It still stuns me.

"The most memorable moment on that set was looking over and seeing Steven behind the camera and realising that I was in a movie being directed by Steven Spielberg and what that meant... and how great it was to have him as the person who said, 'Yes, come and do this.'"