printer quality

[stickerman]

Good day. Language is VB6 (service pack 6)
I have for a while been having a problem that I've tried (unsuccessfully) to get answers to on the Forums (should that be fora?)online.
When I want to send graphics to the printer, I can use the common dialogue box to open the printer screen (for printer choice etc). This, in theory, allows the user to alter some details (e.g. number of copies, colour mode etc). The one thing I can't get it to do is change the print quality (i.e. to request higher quality output).
Last night on line I found, on the Microsoft website a 'print dialogue control'. It stated that this gave more access to printer controls (including print quality). I downloaded and installed the control. There were then 2 sample programs to paste in, to try. The first interrogates the printer and gives details of it's defaults. This showed 'printdlg.printquality' as 720 (dpi).
The second program allows you to alter printer specifications and see the results in the de-bug screen. No matter what I did to the printer, the printer.printquality always came out as 0.
I found the line in the program that says 'printer.printquality = printdlg.printquality'. By pausing the program immediately after this line I checked both variables. printdlg.printquality was '720', printer.printquality was still '0'! (I thought this was impossible). The only thing I can come up with is that there is a bug in VB6 regarding the handling of the printer.printquality item.
Does anyone, anywhere have an answer to this? I am desperately tring to finish a program for distribution, but it has to have the facility of choosing high quality print.
Any help would be appreciated.
Mick.