A pantograph works by having a background image with a "hidden" word inside it. This is accomplished by the background and word being two different line screens, for example one being 150 lpi and one being 133 lpi. A copier will see the higher line screen as denser, and will output it as a solid even though on the original it appears to be the same as the background. I have never seen a pantograph accurately printed on any digital equipment as they cannot produce a line screen that high. I'm not sure if it would work on an Indigo, but you can give it a try. Google "void pantograph", there are several companies that sell the software or already made files. Making one yourself is possible, but not easy. I would email several companies and see if they will send you a file to test. If they are hesitant, ask them to send you a file with their company name, after all, it would be worthless to you except for the test.