HP printers rendering at different sizes

[wyattz]

We currently have an HP Laserjet 9050dn connected to our HP-UX 11.31 server used to print reports. Since the 9050 is nearing end of life we've purchased a Laserjet Enterprise M806 to replace it. Both printers have been connected with JetDirect using the hppi tool. I wasn't the one who originally configured the 9050dn but it's using the net_ljx000 modelscript. The M806 has been installed with the net_ljM806 modelscript. 

I've started printing test reports to the new printer, but it seems that the M806 printer is using a bigger font than the 9050dn. We've kept all of our options the same, such as font pitch, lines per inch, etc. Both printers have their language set to auto in the spool configuration, and the print jobs are specifying PCL as the language. 

Is there some other configuration that would affect the rendering of fonts by a printer that I'm not aware of? I've tried adjusting my font pitch, but even going one number down shrinks the report by a large amount where they perfectly on a page with the 9050dn. 

[Steven Schweda]

   I can't remember ever printing anything from HP-UX, so I know
nothing, but...

> [...] our HP-UX 11.31 [...]

   As usual, showing actual commands with their actual output can be
more helpful than vague descriptions or interpretations.

      uname -a

> [...] I've started printing test reports to the new printer [...]

   What, exactly, are you sending to the printer (queue)?  Plain-ASCII
text?  PDF?  PostScript?  In what form is one of these "test reports"?

> [...] We've kept all of our options the same, such as font pitch,
> lines per inch, etc. [...]

   How/where, exactly, are these options specified?

> [...] Both printers have their language set to auto in the spool

> configuration, and the print jobs are specifying PCL as the language.
> [...]

   Exhibit the "spool configuration".  How/where, exactly, is PCL being
specified?

> [...] the 9050dn [is] using the net_ljx000 modelscript. The M806
> has been installed with the net_ljM806 modelscript.

   Have you compared these model scripts?

[Bill Hassell]

Model scripts are not drivers. They are simple wrappers to add escape sequences before the job and after the job. You need to determine what is mismatched. Is the physical size of the characters (you'll need 10x loupe to compare the font rendering between the printers). Compare these letters:

M W i o O 0

If the fonts are the same, then the character spacing is the problem. This is VERY common among all printers. The horizontal spacing between characters is -o hsi (called leading in the typesetting industry) and the vertical space (kerning) is -o vsi. These can be specified very accurately as real numbers such as -o vsi9.65 -or -ohsi7.3.  The vsi and hsi options are in most of the laser printer model scripts.

There are dozens of HP Laser printers that can print ASCII (the majority cannot and must have the characters turned into bit strings to match the printer's characteristics) but there is no standard to match leading and kerning between printer model.