Digital BW, The Print

> 
> ... I need to know if the MIS
> PKN and UPK are the same optional "Photo Black" inks.

I'm not sure what "UPK" is.  PKN is sold by MIS at this URL:
http://www.inksupply.com/roarkslab.cfm

It is a cooled down PK and not the standard one MIS sells.  It appears that
Epson may have now switched to a PKN for its 2400/4800.  MIS PKN gives a
better dmax than MIS PK, looks better in my view due to its being cooler,
and also seems to have better reflective characteristics (i.e., less
bronzing). 

MIS also has a universal K that is hybrid pigment dye, like the Durabrite K
and probably also the original Epson "Archival" K.  I don't recommend hybrid
inks.

> I have the optional UPK which I purchased with my MIS b&w inkset ... 

It is probably the standard PK.

Paul
www.PaulRoark.com