In 1963, Les and Milly Paris bought a portrait of a Maori boy, painted by Peter McIntyre a purchase that started a life-long love affair with art.

Tonight, almost 50 years later, the couple's private art collection - widely regarded as one of the largest in the country - will be auctioned at Auckland's Art+Object.

In the 1970s, the Wellington couple treasured works by Don Binney, Colin McCahon and Don Driver, before expanding their collection into photography throughout the 1980s and 1990s.

Even after Les Paris died, two days after Christmas 2000, his wife continued to pick up the odd piece to complement the collection.

But now, Paris is moving to Sydney to be closer to her son and grandchildren, leaving behind almost $3 million of art - 225 pieces in all - to be auctioned over two nights, starting this evening.

Highlights include McCahon's North Otago Landscape 6, estimated to fetch $250,000, Family in the Van by Michael Smither, picked to go for about $180,000 and the late Don Binney's Vanishing Wellington Bird, as well as a collection of photographic work and sculptures.

Art+Object director Ben Plumbly said the collection is truly one of a kind.

"There's no other collection like this...they are certainly the most committed collectors I've ever come across. The collection is a testament to Les and Milly.

"We worry about business because we don't see collectors any more that are as dedicated as Les and Milly were. The next generation coming through are not as interested."

The Les and Milly Paris Collection. Auction starts at Art+Object, 6.30pm tonight

- © Fairfax NZ News