Taking Better Pictures - Part 1 "Two, Two, Two Prints in One!" It's true. People can be greedy And that can be good, especially when it comes to photoprocessing. A little greed there can help you take advantage of specials offering two prints from a single negative at a really good price.      Why two?      "People are discovering it saves time and money to have two prints made at the same time," according to Roy S. Pung, executive director of Photo Marketing Association International. "And if you've ever seen two sets of grandparents squabbling over the same photo, you already know the value of getting double prints."      Another reason for ordering two prints at once is economic. The cost of double printing is usually lower than ordering single prints at once-a savings that can be passed along to the consumer.      Double printing is also an effective way of providing prints for both people in a photograph. Fine jewelry representative Pam Schwinn of Minnetonka, Minn., goes so far as to have a print made for each person in every photograph. "I've ordered as many as 12 prints of group shots just to be sure everyone gets one," says Schwinn. "People really appreciate the little extra effort, and the extra cost is negligible."      Multiple prints also make excellent thank you notes for guests at a party. You can personalize them by adding a few comments on the back with a felt-tipped pen.      As a bonus, multiple printing allows you to put one print in the family album and still have one left for framing. No matter how you slice it, double prints make for double fun. And that makes lots of happy people-at a savings that will add up to plenty over the years!