I have to admit I jumped into this thread without back reading the
original earlier postings. I should probably explain something about
the ALPS MD printers. They have two different methods of printing,
depending on which "kit" you use. They come with pigmented ink ribbons
which, although they have variable dot, do work similarly to an inkjet
or laser. They transfer small dots of colored pigment and resin
(actually a thermal plastic/wax) to the paper. This may not require
special receiver paper, but it also may use a special pre-coating on
some papers to give the best result.

When using this system, the printer does use small dots and does dither
them together to create the colors, and it seems to operate at between
600 and 2400 dpi. These prints should be quite fade resistance because
it uses a pigment colorant in the ribbons.

However, this same printer is able to print with dye sublimation
ribbons. In that mode it probably uses a lower dpi, at most perhaps 600
dpi, and possibly less. Dye sub works as I previously discussed,
vaporizing the ink from the ribbon to the receiver paper in different
densities depending on the heat level of the head. As I mentioned, dye
sub heads usually use between 64 and 256 heat levels to make 64 to 256
density levels of color. In this mode, dithering becomes unnecessary
because the dyes are integrated into one another transparently.

I haven't looked at the exact specifications for this printer, so my
comments previously are generalized for most dye sub processes. I
probably should have asked for a definitive answer as to if the dyesub
or the microdot solid ink ribbons are being used, since the technology
is different.

Art