'Not dreamin' - Caton painting a winner

Packed to the Rafters star Michael Caton is now a Packing Room Prize winner.

A painting of the veteran Australian actor took out the accolade in Sydney on Thursday, launching the 2015 Archibald Prize season.

French-born Sydney-based artist Bruno Jean Grasswill beat 46 other finalists to win the favour of the NSW Art Gallery's staff who unpack every entry to the Archibald, Wynne and Sulman Prizes.

Head storeman Steve Peters said Grasswill's multi-coloured "big head" painting stood out the moment he saw it on the first day of submissions.

"He came in bright and smiling. I knew he'd be in the running," said Mr Peters, who has picked every winner since the prize's inception in 1991.

The actor himself was bright and smiling at the announcement in Sydney on Thursday, congratulating Mr Grasswill and thanking the gallery jurors for their "impeccable taste in art".

"It's a bit gritty and a wonderful use of the colours red and orange," Mr Caton said of the painting but he had one jokey complaint.

"The eyes don't follow you around the room."

While the Packing Room Prize pick has never coincided with the winner of the $100,000 Archibald Prize, Grasswill, who up until this painting had every one of his previous entries rejected, said he trusted Mr Peters' judgment.

"Steve's seen more Archibald entries than any art critic, any painter or anyone, he's seen them all," he said.

While the jury snubbed the much-hyped portraits of Jacqui Lambie, two other firebrand politicians, Cory Bernardi and Bob Katter made the cut.

The Archibald Prize winner will be announced on July 17.