Dear Alberto,
I have no real idea except that I'd expect the principle of mathematical scaling to work...
Thus 720dpi = 1/2 1440 dpi along the horizontal axis AND along the vertical axis. (?)
If my assumption is correct then the scale factor will be 1/2 * 1/2 = 1/4
Thus the ink usage will be 1/4 of 1440 dpi.
I have an Epson R300. I always print at 720 dpi. The rare times I tried to compare to the printer's higher resolution I couldn't see any difference with the naked eye... But it certainly took much longer!
No doubt forum members will disagree!
Howard
