Commands for some observing modes, e.g., otfmap, automatically generate ``preview'' plots, see Figure 3.
The range of mapping offsets for these plots can be set with the usual GREG command limits, e.g., enter at the prompt PAKO > :
DEVICE IMAGE W LIMITS 500 -500 -500 500 SET BOX MATCH BOX
Similarly, you can use other commands from GREG to change the color of the plotting ``pens'' or background of the window.