STAMFORD, Conn. (AP) _ Among the colorful photos of children and sports celebrities hanging on Daniel C. Shedrick's office wall is an easily overlooked black-and-white picture that may be the most prized of the batch.

It shows members of the first Bridgehampton, N.Y., Little League team in 1950, including Shedrick, then 8, and teammate Carl Yastrzemski, then 12 and later a star player for the Boston Red Sox.

Shedrick, who is now 44, refers to the picture when explaining why he's president and a founder of a company that's marketing a new, high-tech brand of baseball cards.

''Baseball is a piece of the social fabric of America,'' Shedrick said during a recent interview in his office at Major League Marketing Inc. in Stamford.

Shedrick had been in sports marketing for 15 years before selling his first batch of Sportflics baseball cards last year. That initial production run capped two years of planning and hard work by Shedrick and his partners, who include former Pittsburgh Steelers running back Franco Harris.

Their Sportflics brand was introduced as the baseball-card business boomed, driven by consumers who see cards as a good investment. The company's sales have since soared to a No. 2 share of the retail market, Shedrick said.

Baseball card sales reached about $100 million last year and are growing again this year. The industry giant is Topps Chewing Gum of Brooklyn, N.Y., with about a third of the market. Others in the field are Donruss of Memphis and Fleer of Philadelphia.

While Shedrick wouldn't reveal his company's figures, he said a report that estimated his company's sales at about $10 million in the past year was accurate. He also said his company had experienced a 74 percent jump in sales through May compared to a year ago.

He credits the popularity of his cards to their unique format. Unlike traditional cards, which feature a single color photo on the front, a standard Sportflics has three color photos layered beneath a special plastic coating on the front that create the illusion of motion when the card is tilted.

Shedrick refers to Sportflics as ''high-tech'' baseball cards. Actually, the use of the lenticular process, in which a thin layer of plastic lenses are bound to paper, has been around since World War I. The method was used in the 1970s to create ''3-D'' baseball cards, which gave depth but not motion to photos.

The 3-D cards were produced by Optigraphics Corp. of Grand Prairie, Texas, which now manufactures Sportflics for Shedrick's company. Optigraphics holds the necessary licenses with the major baseball leagues and players to produce the cards.

Sportflics have been well received by baseball fans, card collectors and players themselves. Boston Red Sox pitcher Roger Clemens recently called Major League Marketing to request copies of his cards, which the company supplied.

The cards appear to be selling well, even though they are more expensive than others. Packages of three Sportflics retail for about 59 cents each, compared to about 40 cents for a pack of 15 or 17 cards offered by competitors.

But Shedrick says the lenticular process and need for at least three photos per card results in the higher cost. He believes, though, that the added expense works to his company's advantage and makes Sportflics ''the Rolls Royce of baseball cards.''

Major League Marketing has a staff of 11 people who design the cards, research players' careers and write the information used on the backs of the cards. The company also hires free-lance photographers and selects the photographs used on the cards.

''The average person thinks you get a picture of a baseball player, you get some stats together and then you sell it,'' Shedrick said. ''It's been an extraordinarily work-intensive business.''

In explaining the success of Sportflics and other baseball cards, Shedrick draws upon sociology and economics. Attendance is up at major-league baseball parks, stimulating increased interest, he said.

Also, the growing value of some cards has created a new line of customers: investors. For instance, a Pete Rose rookie card can fetch $450, while a Honus Wagner card is worth about $35,000.

''People collect baseball cards because they enjoy baseball. However, the kicker is that now baseball cards in addition to providing a pastime, a hobby, are an investment opportunity,'' he said.

End Adv June 29