Hollywood star Meg Ryan says the "single-minded focus" needed to be a director was the hardest part about getting behind the camera for her latest movie.
Meg - well-known for her on-screen achievements in the likes of When Harry Met Sally and Sleepless In Seattle - has brought her directorial debut Ithaca to the Edinburgh International Film Festival for its UK premiere.
Taking to the red carpet at the city's Cineworld venue at Fountainbridge, she said she would "absolutely" consider directing again.
But asked about the biggest challenge she faced in the job, she said: "The kind of single-minded focus. When you act in a film you're there for three, four months tops. This was a good long 18 months of concentrating on one thing.
"And I think the biggest surprise was not what I didn't know about directing, but what I did - just by osmosis from being on a film set, acting on a set."
The film, an adaptation of William Saroyan's novel The Human Comedy, is a coming-of-age tale. Described as an elegant Second World War story, it follows 14-year-old Homer (played by Alex Neustaedter) as he delivers telegrams in the early 1940s, with his life changing as he starts delivering bad news.
"The story is very moving to me," said Meg. "It's a story that the author dedicated to his mom. I felt like it was a story a mother could tell and I could bring a perspective to it that would fit the content."
The film also features a small role for Tom Hanks, something which saw Meg reunited on set with her co-star in 90s hits Sleepless and You've Got Mail.
"He's so dear and fun," said Meg, who also takes an on-screen role in Ithaca. "I noticed, taking the film around the world, he is like a goodwill machine. People just love to talk to him and talk about him and he did me a great big favour by being in the film."
Meg also said that being in Edinburgh has helped her understand why the Scottish capital is such a global arts hub.
The US screen star praised the "energy" of the city as she launched Ithaca.
Meg said she was delighted the festival had chosen to feature it in this year's programme.
She told Press Association Scotland: "I understand it now, being here, why the arts come here, and so many different kinds of artists. There's something about it. It's absolutely beautiful but there's a certain type of energy, or a throb, that happens here.
"I feel happy to have brought it (Ithaca) here. You have so many different kinds of arts festivals and it feels like an honour."
Every summer, Edinburgh plays host to a number of world-famous arts festivals - with the season reaching its peak during August.