Good question Adele. Scan all originals “in color” at 300dpi. Do this with in progress drawings as well. I prefer Chartpak AD markers over all others because of the Xylene ink formula – it flows more evenly than the other alcohol based markers. As for markers smearing linework on prints, here is your answer:
1. Stay away from coloring on prints from toner based (that’s the black power used for the print) printers such as xerox and laser printers. The powder that has been heat fused to create the lines will melt from the marker ink.
2. Use printers that have liquid inks – ink jet printers. I don’t have any issues using markers on prints made from those machines.
If you have no choice but to use a toner based printer, skip coloring with markers and use colored pencils.