Betty White’s final on-camera appearance was just 10 days before her death.

The iconic actressdiedlast Friday at age 99, about two weeks before she would have celebrated her centennial year. For the milestone, she had recorded a message for fans to appear in a star-studded film event set to hit theaters on her birthday,titledBetty White: A Celebration.

Steven Boettcher, who produced and directed the special, tells PEOPLE that White was not only in “great spirits” filming her message, but that the recording was also her idea.

“She was great, she was funny, she was the adorable Betty White we all know and love,” he says. “I mean, you see her and you just can’t help but love her and she was amazing — just amazing.”

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“She was really pointed too about talking to the fans and just saying how much love and admiration she has for them, and it’s so sincere, she really meant it,” he adds. “And this was her idea to do this little video. It was not our idea, so I think that even makes it more special.”

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Boettcher also says White was “looking amazing” when she sat down to record the video.

“It’s very, very sweet,” he says. “She was excited about getting dressed up, too, and getting glammed up.”

Boettcher and his fellow producers previously announced that they weregoing forward with their plansto release the film on Jan. 17, what would have been White’s 100th birthday.

The film willfeature Whiteas well as her various celebrity friends, includingRyan Reynolds,Tina Fey,Robert Redford,Lin Manuel- Miranda,Clint Eastwood,Morgan Freeman,Jay Leno,Carol Burnett, Craig Ferguson,Jimmy Kimmel,Valerie Bertinelli,James Corden, Wendy Malick, andJennifer Love Hewitt.

It will also showcase clips from her long career in Hollywood, from her early role in a 1950’s sitcom toGolden Girls, Hot in ClevelandandThe Proposal.

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Boettcher says he had been working with White on the project for the past 10 years and grew close to her during that time. He describes the finished film as “just truly Betty.”

“People getting together and celebrating Betty is really the most important thing and the reason we went forward with it, because Betty would have wanted it,” he says.

Betty White: A Celebrationwill be in select theaters for one day only on Jan. 17. Fans can buy tickets and find local theaters atFathomEvents.com.

source: people.com