Digital BW, The Print

To Clayton & Ernst

If my (perhaps sloppy) terminology about printing the "black plate"
confused you, apologies again.  What I meant was, if I print a
monochrome image, either grayscale or RGB, with the Epson 2100 print
driver set to Black rather than Colour, then the print is too light
either way.  In trying to understand what was printed, if I take
either version of the monochrome image and convert it to CYMK in PSCS,
and compare the black channel to the corresponding print, it is an
exact match.

The print from a RGB monochrome image was the lightest, and exactly
matched the black channel in a CYMK version of the RGB image.  A print
from a grayscale version was darker but still not dark enough, and
again matched the black channel in a CYMK version of the grayscale
image.

I don't know what the Epson printer driver is actually doing, but it
looks like it is taking each image, converting it to grayscale, and
print *only* the black channel.  I thought BO was supposed to print
*all* the channels using the black cartridge.

Reponses to your questions below.

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Clayton Jones" 
<cj@c...> wrote:
> My first thought is if the back end is "Same As Source" and 
> the print is too light, then the front end profile is incorrect.  
> What is the front end profile now?

The grayscale image is tagged as Dot Gain 20%.  The monochrome RGB
image is AdobeRGB.
 
> Try different front end profiles until the screen image matches the
> print

If my description at the front of this reply makes is comprehensible,
then you'll understand why I don't think that this makes any sense.  I
can change to any dot gain I like, convert to any profile I like, but
the black channel when I convert a copy of the image into CYMK mode is
virtually the same, and this is what the print using the Epson driver
set to Black will look like.

> With a loupe can you see only black dots in the print?

In the BO attempts, yes.  Only black dots.  Whereas in a full-toned
QTR print there are slight traces of magenta and cyan.

> Mine says "Black Ink Only".  Here's a screen shot (version 5.40)
>      http://www.cjcom.net/files/2200props.gif

The 2100 driver looks different.  Look at 

  http://www.photo-i.co.uk/Reviews/interactive/page_13.htm, 

particularly the two advanced setting photos in the third row of
images.  Note the choice between either "Color" or "Black".  The
context help for this option says that if you choose black, colors are
converted to grayscale, which is not exactly what I experienced.

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, Ernst Dinkla 
> The other choice is BO printing only which is 
> using the K channel only from 0-100%. Some Epsons don't have that 
> last choice in practice. 

I'd hardly call it a choice.  No selection of channels or percentages

> Wasn't there a difference between 
> European and US drivers on that option ?  

There seems to have been.  

> Getting a loupe to check which channels are 
> actually used may clear things up, even the shadows.

It's only printing from the black cartridge, and it's only laying down
the amount of ink specified in the black channel of a CYMK version of
the image.

More puzzled than ever, but it's got to be the 2100 driver.

F_P