Digital BW, The Print

Hi :)

So I've tracked down some of the problems I was having - first a bad
cartridge, then a monitor that was miscalibrated so I wasn't getting
an accurate sense of my tones.

Now that those are behind me I think I'm more or less clear on how
this system works - but I'm still finding that I have problems getting
the look of continuous tone. The neutral curve I'm using (the mac 1280
curve) works pretty well, although I get some posterization in the
darker midtones. The medium warm and warm curves (again 1280 mac
curves) however sometimes give me severe posterization. 

Here is my process:

I open the image - either it is already 16-bit greyscale, or it is
16-bit color, which I then convert to greyscale using the channel
mixer.   
Once I have a 16-bit greyscale file, I fiddle with the curves and
levels until it seems correct, and then I convert it to RGB using the
Adobe RGB working space. (If it started as RGB and was converted with
channel mixer, it stays an RGB file the whole time, but I make sure
the profile is Adobe RGB) I then apply the 1280 curve and print using
these settings:

I am printing on EAM

Working Space: Adobe RGB
Print Space: Same as source
Paper: PQIJ
Resolution: 1440
Microweave is on
high speed is off
Color Controls are activated, all sliders at zero, "Auto"
Gamma is 1.8

I also tried using the 1270 curves with sRGB colorspace and all other
settings as above, results were almost identical.

I'm totally willing to believe the problem is with my files, but I
could use some advice about how to fix it.

thanks much,

Charles Bandes