Digital BW, The Print

Here's my understanding...Ernst please correct me if I am wrong.

You can of course still profile the printer for colour in the normal fashion
(print a test target, measure the results and then compute the ICC profile).
Typically this is done with No Colour Adjustment set in the printer, ie the
printer simply renders the RGB file numbers without adjustment.  The
controls in the driver (eg the sliders) effectively "calibrate" or tweak the
printer.  One can create a profile which is specific for some set of
driver/printer calibration, eg a profile specific for a particular set of
calibration controls set in the driver.   This profile would only be good if
those controls are set at the same as when the profile was made.

This is fine for colour work.  But I am not so sure about the B&W controls.
The B&W controls take a colour RGB image and convert it to B&W, or take an
existing greyscale image, and then allow the user to set certain printer
calibration features (eg tint) to render the image.  It sounds like it may
also use a different set of lookup tables than for colour.  If one wanted to
get an accurate soft proof of a particular set of calibration controls one
would normally, as described above, print a test chart with those controls
set, measure the results and generate the profile.  Unless I am mistaken, I
think most profiler software will error out in trying to do this unless some
accommodation is made via a new profiler software release and test chart.
For example, think of the process of using Eye One Photo to profile an Epson
printer.  You print the test chart and measure the results.  If the results
differ too much from expected then the software errors.  The test chart is a
set of colour patches.  The output will be in B&W mode a set of greyscale
patches.  I think it will bomb out.

Linearization is a different (but related) issue.  It is rather rare (as far
as most people are concerned) that a profiling package will test for
linearization first and then construct a new test chart which takes the
printer's linearization profile into account.  I do not expect Epson to
allow us to tinker with the printer's linearization.  Sometimes a lack of
linearity is better than perfect linearization when it allows the gamut to
be extended.  Non-linearity is taken account of in profiling.  I suspect
that Epson decides what it believes the optimum linearity/non-linearity is
and sets it accordingly.  The references in the reviews to linearity suggest
just two things: they have decided that more linearity is better (making it
easier for profiling) and the pro models are individually tuned to a
particular mix as they come off the production line whereas the 2400 is not.


> From: Ernst Dinkla <E.Dinkla@...>
> Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Date: Mon, 16 May 2005 12:07:40 +0200
> To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> Subject: Re: [Digital BW] New Epson Printers
> 
> Roy wrote:
> 
>> Steve Kale wrote:
>>  
>> 
>>> I'm just coming up the CMYK learning curve but this seems a little worrying
>>> to me - being dependent on the Epson driver canned profile for a decent B&W
>>> profile rather than being able to generate a "custom" profile with third
>>> party software like the Eye One.  I suspect the B&W community needs to dig a
>>> little deeper into just how this part of the Epson driver works.
>>> 
>>> 
>>>    
>>> 
>> 
>> 
>> I'm even newer coming up that curve, but am I hearing this right that
>> there's no way at this point to make profiles for the 2400
>>  
>> 
> 
> For RIPs and the Epson driver there will not be any problem to make
> custom color profiles, CMYK or RGB.
> There's doubt about the possibility to linearise the B&W output of the
> printer driver.  Of course one could correct that part with curves in PS
> if it isn't satisfying.
> 
> Ernst