The Fergusons' private collection reflects their talent-spotting skill, and now they're sharing their treasures, writes Aidan Dunne.

Relatively late in his life, the painter Patrick Collins took a new and, to his admirers, unexpected direction in his work. Toward the end of the 1980s, he began to make what he called cut-outs: paintings of irregular shape, canvases to which he had, literally, taken a scissors.

Characteristically terse and oblique when it came to explaining himself, he wrote, in a brief catalogue note at the time, of his long-term artistic aim: "I started by trying to wed the thing and some hidden meaning of it and instinctively demanding a shape that overall accommodated them both."

It seemed a logical development, to him, that the shape of a painting should not be fixed and uniform. The blank spaces in his cut-outs represented what he did not know. To paraphrase Wittgenstein, the limits of his painterly language were the limits of his world. At the same time, Collins had become intrigued by Chinese painting, and expressed admiration for the way Chinese artists had a viable alternative to the classical perspective of European painting, and their sophisticated use of space in composition.

He started to use line, often in spiral patterns, and strong colour, much more prominently than heretofore.

Even his most enthusiastic fans were taken aback. They were used to a more muted Collins entirely, a painter of misty, soft-edged landscapes. The jagged urgency of his cut-outs was simply too much. Not, though, for Vincent Ferguson, a businessman and art collector, and one of the painter's staunchest supporters for many years.

"I just loved them," he recalls now. "Here was Paddy, in old age, and suddenly all this colour came into his life. It looked as if he had an entirely new vision. I think it's something that seems to happen to painters. Look at Tony O'Malley when he went to the Bahamas, for example."

A group of Collins's cut-out paintings form the core of The Vincent and Noeleen Ferguson Collection, an exhibition at the Model Arts and Niland Gallery in Sligo. Ferguson is particularly delighted that the cut-outs occupy centre-stage. It is, he points out, the first time they have shown in any number since they were originally exhibited in the Tom Caldwell Gallery in Dublin. "People", he observes wryly, "still haven't really caught onto them."

The Model Arts show features work by just five artists: Collins, Basil Blackshaw, Charlie Brady, Brian Maguire and Kathy Prendergast. Ferguson and his wife, Noeleen, have acquired substantial holdings of work by all of these artists, and indeed many more.

The passionate enthusiasm with which Ferguson speaks of the work is a useful corrective to the current vogue for viewing art purely as a commodity for investment purposes.

In an eloquent, perceptive essay accompanying the show, Ferguson's daughter Ciara writes about growing up with parents who were avid art collectors: "Dad lived in the world of business, but he breathed the world of art" and, she notes, he preferred the company of artists to that of business people any day.

Time and again he bought paintings because he was simply swept away by something in them. Certainly, judging by what is on view at the Model, he has a knack for seeing beyond the obvious.

He realised very quickly, for example, that Prendergast was an exceptional talent, and bought her series of extraordinary body-map water-colours from her graduate exhibition.

But he also followed her into more difficult areas, buying the works on show in Sligo, a set of dreamlike works exploring embodiment.

In 2001, Basil Blackshaw embarked on a series of Windows paintings. He is an artist with an exceptionally loyal following, but even so many of his fans have struggled to come to terms with the minimalist nature of the Windows and the subsequent works arising from them, shorn as they are of the rich, anecdotal content normally associated with what he does.

Ciara Ferguson remembers her father seeing them for the first time when they were exhibited at the Ulster Museum in Belfast in 2001. There was, she says, a euphoric look on his face. "He was almost bursting with excitement and wonder."

"They just stood out for me," he recalls. He hasn't bought much in the recent past, and he didn't intend to buy anything when he went to Belfast. "But they seemed so exceptional. Everything else had been sold and I thought, I can't let the opportunity pass, by hook or by crook I had to get them." His instinct was sound. The Windows are brilliant paintings that occupy a central position in Blackshaw's oeuvre. They are physically substantial, and they are extremely well served by the space in the Model.

What has grown to be one of the leading private collections of Irish art began indirectly. "I thought I'd buy something because the walls were bare," Ferguson recalls. He bought reproductions of paintings by Monet and Vermeer. "They cost two pounds and ten shillings each." The experience enlivened his eyes and he began to notice art in a more alert, critical way than before. He and Noeleen began collecting in earnest in the 1970s.

Ciara distinguishes a division of taste, or perhaps responsibility. He is driven by "an intense curiosity . . . a need to absorb and understand more". Noeleen provides a counterbalance, "intuitive to the kinder side of life, dreamy portraits and watery landscapes".

The Fergusons are a breed of collectors who are driven not by potential financial gain, but by a deep engagement with and love for the art they acquire. As Ciara pointed out, the enthusiasm for art extends into a curiosity about artists. "The person is important," Ferguson acknowledges. He is acutely conscious of his Sligo background, and was particularly aware of the importance of Sligo for Collins. "Like Yeats, he enjoyed an idyllic period here during his childhood and, like Yeats again, he was wary of going back."

Eventually Ferguson prevailed upon him to revisit. "He was delighted. We brought him to Lough Gill, where he played as a boy, as he found it was still wonderland for him. We had him out to the house at Rosses Point, and my abiding memory of him is sitting on a tree stump down at the end of the garden, looking out to sea and thinking about the past."

Brady he remembers fondly as "a typical, laconic New Yorker in a trench coat mysteriously transplanted to Ireland. Basil told me he met him once in the art suppliers, Kennedys. They were both buying canvases, but where Basil needed a van, Charlie just had a neat little bundle under his arm. And, Basil said, the galling thing is that he was probably going to off to paint a bunch of little masterpieces. I think a lot of Charlie's paintings are just that: little masterpieces."

Blackshaw, who has a aversion to exhibition openings, came to see the Windows in Sligo. Ferguson recalls the painter showing him another spare, monochromatic Window in progress in his studio. "He said: 'What do you think?' And I said, 'it's lovely Basil, but maybe a little glimpse of blue sky in the corner and perhaps a bird or two flying across.' He absolutely blanched. For a second he thought I hadn't got the point at all of what he was trying to do. Then he nearly fell off his chair laughing."

Did Blackshaw elaborate on what he set out to do with the Windows? "Well, he did actually. My understanding is that he sees the windows as a kind of culmination of his painting. What he said is that everything is nothing, and nothing is everything. He talked about developing them further, of getting the vision without the windows."

Ferguson's eyes light up. He is not, as he says, buying much these days, but you can tell that if Blackshaw gets around to paintings that dispense with the windows, he simply may not be able to resist.

The Vincent and Noeleen Ferguson Collection is at the Model Arts and Niland Gallery until Feb 12