Film positives will always work best when they are dark and opaque to block the light source during exposure. We use waterproof ink jet film for our film positives. We print the film positives with an Epson 1430 inkjet printer. We also use Blackmax ink in our Epson- Blackmax also us to fill all of the ink cartridges with black ink. Whatever printer you use- just make sure you get dark opaque film positives. We also use UltraSeps color separation software to separate our art before printing film posiitves.