Printronix ThermaLine Series - Manual (Page 55)

4–11 Commands
Because of the second hammer bank stroke required to plot the extra
columns of dots, print speed may be reduced up to half when the DARK
parameter is used with Bar Code commands. However, this decreased print
speed should be weighed against the significant increase in bar code PCR
and extended ribbon life.
NORMAL MODE
ADDED COLUMNS OF DOTS
DARK MODE
Figure 4–2. Dark Printing
NOTE: Depending on the printer used, the printed appearance and location
of your print samples may vary from to those shown in this manual.
The position of your print samples may also vary compared to these
examples, depending on the initial print position.