Set Printer Feature programatically

Hi, I'm working on a C# desktop application where I need to change some printer settings and print some pictures. In my program I already can set the Paper Size, Printer Name, etc... If I go into the Advanced Options of the printer preferences, there is a section called "Printer Features". I cannot figure out how to access the parameters in the printer settings. For example there is "Print Quality", "Print Density", "Continuous Mode", etc..

Attachment 30789

Does anyone know how I can get at these properties in run time?

Thanks.