I have been trying to figure out why the IBM graphics printer has a higher dpi in quadruple density , than the Epson MX-80 since technically the IBM graphics printer is a rebranded version of the MX-80.
Both printers have the same dpi resolution for single density and double density graphics mode, but when it gets to quadruple density the dpi is different vertically. The MX-80 in quadruple density mode has a resolution of 240 x 144 dpi , while the IBM graphics printer is 240 x 216 dpi.
I am guessing if the IBM graphics printer can do 240 x 216 dpi , so probably can the MX-80. Maybe there isn't a difference in print quality when printing with those resolutions? I know the print head is 72 dpi vertically, and has to overlap the dots to get 144 dpi, to get 216 dpi I am guessing the dots have to overlap even more?
Someone on here probably knows a correct answer to why the quadruple density is different on these printers even if they are technically the same printer.