Printronix t8000 Administrator's Manual page 68

Adjusts the vertical print resolution. This can be used to compress or expand
all printed forms by small amounts.
Minimum
Maximum
Factory Default
68
Media > Image > Vertical DPI Adj
195 (203 DPI)
290 (300 DPI)
210 (203 DPI)
310 (300 DPI)
Match Head DPI