The database that stores information on 1800 works by Colin McCahon is old and failing. Kim Knight speaks exclusively to grandsons Finn McCahon-Jones and Peter Carr about an ambitious plan to save and expand the artist’s legacy. Everytime he looks at the painting, he sees something else.

Fingermarks on the selvedge of the canvas: “Like small landscapes - I hadn’t noticed those before.” Finn McCahon-Jones is small against his grandfather’s artwork. It’s a preliminary version of McCahon’s Urewera Mural (a painting that will, one day, make major headlines) and the massive three-panel piece fills an entire wall of a private room at Gow Langsford Gallery Onehunga .

His eyes move across the canvas. “Who needs a television?” “I tell you what you would need,” observes his cousin, Peter Carr. “A very big wall.

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