Buying signed art is terrific - for an autograph collector. Artist's signature may enhance investment value, but it's iffy

Several years ago, the late Andy Warhol sat down and signed his name to copies of Interview, the tabloid magazine he founded. The magazine costs $2, but he charged $50 for these signature copies, and they sold fast. As with much of Mr. Warhol's work, he wanted to demonstrate how gullible people can be - specifically, those who would believe his name had value in and of itself.

The art print market is one where signatures count for a lot, and hundreds of artists have jumped on the bandwagon. An artist's name on a print can bring up the price by two or three times, and artists generally view signing and numbering works as a valuable source of income.

Many artists and dealers contend that by signing a print the artist approves and endorses it, implicitly claiming it as his or her own work. But in most cases, artists have little involvement in the technical process of printmaking.

In some cases, the entire economic value of a print is in the signature. Salvador Dali signed blank pieces of paper on which reproductions of his works were printed. So did Marc Chagall.

Pablo Picasso's granddaughter Marina published a series of the artist's prints to which she signed her name. In these cases, the artists never saw the finished works, but the prints still sell at prices that would lead one to assume they are original works of art.

``A signature has a certain cache, and some buyers believe that a work with the artist's name on it has some investment value,'' says Nicholas Stogdon, former head of the print department at Christie's auction house in New York.

``The real issue is, however, what kind of print it is and the degree to which the artist was involved in its production. The secondary [resale] market of most signed prints is poor, and Christie's tends to deflect inquiries whenever possible.''

Mr. Stogdon notes that an ``original print, where the artist worked on it,'' has a longer-lasting value than a ``reproduction which the artist did no more than sign.'' Etchings and lithographs, for instance, require artists to design the plate from which impressions are taken.

A photographic reproduction of a work of art, sometimes called a colotype, is a far more questionable print in terms of its originality, since it is the product of advanced four-color printing techniques.

Stogdon says that in almost every case a colotype should not cost as much as an etching or lithograph, ``unless you believe there is something magical in the mechanical process.''

Most artists are aware that their signatures mean more money for their works.

``A Picasso with a signature may be worth twice as much as one without a signature,'' says Mark Rosen, head of the print department at Sotheby's, the New York-based auction house.

He notes that Picasso did a series of etchings in the 1930s called the ``Vollard Suite,'' which he started signing in the 1950s and '60s as a way of increasing contributions for communist causes he championed.

Norman Rockwell signed a series of photographic reproductions of his paintings to help support the Cornerhouse Museum in Stockbridge, Mass., which features his paintings. Andrew Wyeth also signed reproductions for fund-raising events. Other artists have less philanthropic uses for the money.

A signature can be misleading at times, when it has been printed onto the paper along with the artist's name. One needs to look closely when a dealer claims that the print has been ``signed by the artist.''

A signature alone may cause a buyer to overlook a variety of issues that are important - not the least of which is the price.