But the two worlds were brought together at the National Gallery of Australia this week, when actor Simon Baker visited for a private preview of its Tom Roberts' retrospective, ahead of its opening on Friday.

The self-confessed art-lover liked what he saw, but was initially less keen on Canberra. When asked what he loved about the capital he replied "it's not far from Sydney, it's a pleasant drive."

The zinger drew laughs from the crowd, and a shout of "ouch", but he redeemed himself when he praised the "amazing" city as the country's "arts and culture hub".

"I'm not here as a politician, I'm not here as an art historian, I'm here as a general punter," he said.

"To see his works in person and to see a reflection of all the aspects of our identities as Australians shone back at us, not just with the Tom Roberts' exhibition but also with the indigenous art and the magnitude of the collection here, is profound."

Baker said Australians didn't have to be art snobs to want to see art and be affected by it personally.

The NGA has recruited Baker as a new ambassador to appeal to a different demographic, and more stars are expected to join the ranks to spruik the gallery as it recovers from declining audience numbers, director Gerard Vaughan said.

"A lot of museums around the world have ambassadors, well-known people, celebrities who stand up and say this is worth coming to look at," he said.

On Tuesday night, Baker had a first look at the summer blockbuster and a 2.5-hour tour of the newly-refurbished and re-hung Australian and International galleries, before a media event on Wednesday.

He said it would take more than one day to see the entire NGA and he expected to return to see the rest.

There were some art-lovers at Wednesday's event who admitted they didn't know who Baker was, Vaughan noting they obviously hadn't watched The Mentalist.

The Roberts' retrospective, featuring more than 130 works from the artist's 60-year career, marks the gallery's renewed focus on Australian art with a reshuffle bringing it down to level one.

Vaughan said the gallery's first summer blockbuster featuring an Australian artist was an "experiment" he hoped would attract up to 150,000 visitors and so far pre-sales and inquiries suggested it would be "very popular".

Baker said he first encountered Roberts growing up in his hometown of Ballina on the NSW north coast, where he recalled seeing a print of Shearing the Rams in the library.

He dismissed the suggestion the younger generation might see Roberts as "old-fashioned art", saying he gave hipsters more credit.

Baker praised the gallery's touring program visiting regional areas, saying the first time he became engaged with art was when an HSC art exhibition toured.

Despite many of Roberts' works being familiar from the usual homes in other Australian institutions and public galleries, Vaughan said the retrospective was a chance to see it all together.

"Why would someone go to a big Monet exhibition when they can see Monets in London, Berlin, Amsterdam and Paris? By having them all together you begin to understand the artists' career," he said.

Vaughan said when the gallery expanded it would hang the Australian collection in natural light, but funds from the federal government were yet to come through.

Chief minister Andrew Barr said he was a big supporter of the gallery's second stage development, but it was outside the ACT government's remit to fund the expansion.

Baker is not the only celebrity to visit the gallery in recent days.

On Tuesday night the gallery hosted British artists Gilbert and George, known as the living sculptures, and in perhaps another attempt to spruik the Roberts' show gave the artists a copy of the blockbuster's catalogue.