Creating a CUPS printer instance from web interface?

[Laszlo Nagy]

I would like to create named instances for an Epson printer. We are 
printing invoices on normal A4, photos on glossy photo paper, and draft 
papers (with draft quality). E.g. the paper size, margins and print 
quality changes from time to time.

I have two problems. First, I do not see any way on the CUPS web admin 
interface to add printer instances. I only have 'set printer options' 
but it does not allow me to create instances.

The other problem is that lpoptions lists the options, but I do not know 
their meaning and the possible values. Example:

gandalf at gandalf-desktop:~$ lpoptions
media=A4 finishings=3 copies=1 job-hold-until=no-hold job-priority=50 
number-up=1 auth-info-required=none job-sheets=none,none 
printer-info='EPSON Stylus Photo R265' printer-is-accepting-jobs=1 
printer-is-shared=1 printer-location printer-make-and-model='Epson 
Stylus Photo R265 - CUPS+Gutenprint v5.0.2 Simplified' printer-state=5 
printer-state-change-time=1227085737 printer-state-reasons=paused 
printer-type=8556556

Which option is for printing quality? What are its possible values? It 
depends on the driver, and therefore it is not covered in the CUPS 
manual. The drivers themselves does not have a documentation. So where 
can I get this information?

Thanks,

   Laszlo