QTR-Quadtone RIP

Thank you both for your reply. MIS sounds very interesting as well. 

What if I just skip the QTR RIP software and use the standard print command.. (As suggested by the German Carbon ink reseller). Then I still don't understand one thing; if I would like to print with these carbon inks (MIS carbon inks or German Carbon ink 8 shades) and do this just with the standard print command from within Photoshop: how does the printer software know that it can print with all 8 ink gray cartridges? If I would insert K3 inks, it would pick black, the 2 shades of grey (LK, LLK) and perhaps some color to mix grey values.. But how does the print software know it does have not K3 but a whole range of Carbon grey shades to choose from?