Mr. Link hails the train

The artist in O. Winston Link is well-hidden beneath a thick crust of avuncular, all-American down-to-earthness. What do fashionable people like actress Diane Keaton see in him?

He's the sort of man you expect to find enjoying a piece of pie in an all-night cafe off the lower reaches of Broadway at an unrespectable hour. And find him there you would, for he likes those kinds of places, and he keeps those kinds of hours.

But there is another side to Winston Link which the fellow he sits next to in the all-night diner would never guess existed beneath Link's determinedly Brooklyn exterior.

And that is O. Winston Link, art photographer of recent renown, whose series of black-and-white photographs of the now-extinct steam trains on the Norfolk & Western Railway in the eastern United States has the international photographic establishment reaching for superlatives. New York's Museum of Modern Art, London's Victoria and Albert Museum - and Hollywood's Miss Keaton - are among the purchasers of the drive-in movie photograph seen on this page.

Yet the pictures now exciting attention in New York, London, and Paris were taken 30 years ago, and their negatives have for the most part lain dormant in a bank vault beneath the Empire State Building.

For O. Winston Link is the quintessential example of a man who did something he wanted to do, not for fame, or for money, but because he loved it. That attitude has produced work of an artistic intensity which highly paid photographers in their sky-lit studios might never achieve in a lifetime of more calculated effort.

Financed by the money he made as a successful industrial photographer, Link poured a colossal portion of his own time, effort, and funds into taking more than 2,000 photographs of the trains he loved. And though it increased the technical preparations tenfold, Link decided the best time to photograph his trains was at night.

Now he's getting his due reward as someone who was always much more than merely a train buff with a good knowledge of photography. He has had a one-man show this summer in London, which attracted wide critical applause, and a major Link exhibition is in its final days at the International Center of Photography in New York before moving on to the Chrysler Museum in Norfolk, Va.

''I've never seen anything like his work,'' said Rupert Martin, exhibition director of the Photographer's Gallery in London, who launched Link's work there. ''It's unique and it works on several different levels. It works for railway buffs, for people interested in photography, and then there's the strictly human level. His pictures allow you to involve yourself in the lives of Americans in the 1950s.''

Link's initial decision - to take most of the photographs at night - brought the huge complications of lighting each scene for flash. Often he had only one chance to get the picture right during the few seconds in which the train he was waiting for passed by. But the night effects added power and intrigue to Link's results - and proved to be a way of showing off the white smoke of the steam train to beautiful advantage.

The trains course through the Winston Link series, past junctions, through towns, over bridges, gathering a strange cumulative significance.

However close the steam trains pass, they are largely unnoticed by the local inhabitants. In one picture, the train passes literally feet from a family's living-room window. Only the little boy acknowledges it with a wave; the mother gazes off elsewhere. In another print, children splash and swim in a stream beneath the railway bridge, oblivious of the train overhead. It's as though the train represents a different reality, barely perceived by them but very near.

In ''Hot Shot Eastbound at Iaeger,'' Link symbolically depicts the demise of the steam train. People have come to the movie in their 1950s cars (the transportation of the present) to watch an image of the airplane (the transportation of the future) as a steam train steals past in the background, chugging unnoticed toward obsolescence.

Link guarantees that the image of the plane was genuine - it really did appear on the drive-in screen that evening. But he says it has to be printed separately and superimposed on the screen in order to produce a clear image.

In ''Birmingham Special at Rural Retreat'' Link has produced his most emblematic photograph. The Rural Retreat station becomes a stage set, and the train the long-awaited star. Link has lit the scene to achieve the most dramatic effect. Ignored by the locals in many of Link's pictures, the train is appreciated in Rural Retreat.

Link achieves what all photographers strive for but few succeed in doing: turning life into memorable images. At first glance, his photographs seem to encapsulate an intensified view of an era of ordinary American life. It is only when they are studied a bit longer that the photographs reveal images that approach surrealism - brought out from the veneer of the commonplace by Link's piercingly artistic eye.

All this was not technically easy. Link tells horror stories of traversing waterfalls on self-made wire bridges to string lights for a picture. He would often use literally miles of cable and dozens of bulbs for just one shot. He sometimes waited hours in the dark and cold for a particular train to pass by. And though he had to ask innumerable favors of local people and the Norfolk & Western staff, he says that one of the most remarkable aspects of the project was that he was always treated politely, and his requests, if they were humanly possible, were granted.

Today, Winston Link is approximately 68 (''I often forget how old I am,'' he says, and his year of birth is uncertain) and semi-retired in the house in which he grew up in Brooklyn. He spends every spare moment working on restoring a steam locomotive which he keeps in New Jersey.

Fame has come too late to Winston Link to spoil his mischievous eccentricity and down-home wit. He is undeniably pleased, though, that the artistic establishment is now recognizing him, and that his work will last.

This is satisfying to know, Link says, when he has relatives like his sister-in-law, who often insisted on wondering out loud: ''Why did Winston waste his life taking those photographs?''

It gives him something to chuckle about when he's eating his pie in that all-night cafe, or enjoying his favorite ice cream in that Howard Johnson's in Rockaway, N.J., en route to a day's work on his very own pet locomotive.