Digital BW, The Print

I am new to printing high quality black and white pictures. I recently
bought a MIS Variable Tone ink cartridge for my Epson 1280. I tried to
follow the instructions on the MIS web site very carefully and use the
curves by Paul Roark, but I'm getting weird tones on my images.

I've been using the regular Epson black ink with the MIS 6 color variable
tone cartridge. I just want ask if my problem is that I need to use a black
cartridge from MIS, or if there could be a different problem?

I'd be happy to scan the printed image to show you what I mean by "weird
tones" (sorry I can't put my finger on it verbally) but I'm hoping someone
has experimented with this, or made this mistake and can let me know for
sure.

Thanks,
Ericka Menchen
www.erickamenchen.com