Painters of the Great Outdoors. A day in the sun for long-neglected landscapes of the Hudson River School

JUST a bunch of pretty landscapes - by a handful of sentimental romantics. That was the kind of condescending judgment historically accorded the American artists of the Hudson River School (1825-75). Celebrated in their own time but eventually regarded as old-fashioned, the wild and rural imagery of artists such as Frederick Church, Thomas Cole, and Albert Bierstadt was virtually ignored until as recently as the 1940s.

Now, however, these painters of the great outdoors have come in from the cold.

``American Paradise,'' at New York's Metropolitan Museum of Art, is a kind of official vindication of the Hudson River School's artists, philosophies, and achievements. It is the first full-scale exhibition of the school in more than 40 years, bringing together 86 of that group's finest and most famous landscapes by 25 American painters of the mid-19th century.

This is an expansive display, with huge, panoramic canvases of sunsets in the Rockies, the Andes, and the Hudson River Valley; magnificent vistas of rivers meandering into the distance; dense and richly detailed forest and jungle interiors; and spectacular glimpses of hidden mountain streams and valleys and vast, open plains.

THESE works now fetch prices as awesome as Church's mammoth ``Niagara.'' Canvases that sold for $1,000 in the 1940s, and then for $10,000 in the 1960s, went for considerably over $100,000 during the 1970s. Church's monumental picture ``The Icebergs,'' for instance, had it come on the market in 1910, would probably have realized $1,000 at most. In 1979, it was sold at auction for $2.5 million.

This kind of attention would certainly have been unimaginable to the artists themselves, even though several of them - Church, Bierstadt, and Jasper Cropsey, in particular - became international celebrities while still relatively young, achieving for a time the kind of national reputations of which most painters can only dream.

It all began with Thomas Cole (1801-48), America's first popular landscape painter, and the artist acknowledged to be the father of the Hudson River School. He was born in England, came to the United States with his family when he was 17, and was a recognized talent by the time he was 25. The effect his early work had on New York's artistic community was summarized by his friend William Cullen Bryant: ``Here, we said, is a young man who does not paint nature at second hand, or with any apparent remembrance of the copies of her made by others. Here is the physiognomy of our own woods and fields; here are the things of our own atmosphere; here is American nature and the feeling it awakens.''

Cole's vision of the American wilderness as a new Garden of Eden, with features that were both sublime and beautiful, was shared by Durand, his artistic heir and the other dominant talent of the school's first generation of artists. Although less inclined to the spectacular than Cole, Durand also favored lofty themes, especially if they were imbued with a subtly elevated moral tone.

CHURCH's ``Niagara'' (1857) was that artist's first major success, and the work that announced the emergence of the school's second generation of painters. The latter's vision, which tended to be considerably more expansive and theatrical than that of their predecessors, was also occasionally inclined to call for foreign and distant subjects. Church achieved his greatest fame with panoramic views of lush tropical terrain; Bierstadt made his name with huge paintings of the Rockies.

With the end of the Civil War, and the growth of a new cosmopolitanism, American tastes in art began to change and the school went into rapid decline. Only George Inness, who was influenced more by the French painters of the Barbizon School than by Cole or Church, achieved any real success. Most of that success, however, came to him during the 1880s and '90s, when the reputation of the Hudson River School had fallen to its all-time low.

All that, of course, has recently changed for the better. The school's legacy remains intact, and its reputation is higher now than at any other time in this century.

``American Paradise'' was organized by members of the Departments of American Art at the Metropolitan Museum of Art, and consists of works drawn from the museum's holdings as well as from other public and private collections. It is at the museum through Jan. 3.