Printer Margins/Sizing

[Anonymous]

Oh yeah.  /etc/papersize is set right, I've restarted the CUPS server after making changes, and I've even rebooted many times.  I also made some additional changes to the .ppd file, changing

*ImageableArea Letter/Letter: "18 36 594 783"

to

*ImageableArea Letter/Letter: "12 12 600 780"

but the problem persists.  Nothing I do to any configuration file seems to make any change at all in what comes out of the printer.

> Would someone be kind enough to show diagram how CUPS printing works?  (Or send me a link to the page?)  I'm hoping if I get a better understanding, I can fix my problem:
>
> The margins of my printer are set wrong.  (It prints out this certain pdf file right in Windows, but not in Linux.)  I've used alignmargins to change my ppd.  I made sure I have up-to-date everything.  I have the recommended ppd for my printer.  (I have an HP Inkjet which is considered "well supported.")  I tried changing /etc/cups/lpoptions, I tried invoking lp with different command line options, and I tried changing options in kprinter.  I tried with five different pdf viewers (acroread, xpdf, gpdf, kpdf, and something else I forget now), each time printing once through lp and once through kprinter.
>
> In all these cases, the outcome was exactly the same.  The result:  each one is off centered and some of the pdf file has been cut off in exactly the same way.  Apparently, none of different things I modified have any affect on the outcome.  And since I know things work perfectly in Windows, I just must have a fundamental misunderstanding of how the printing configuration files work in CUPS.
>
> Thanks for any help.