Digital BW, The Print

From: "Jean-Marc Humbert" <humbertjm@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Monday, June 02, 2003 5:43 AM
Subject: [Digital BW] PiezographyBW, custom dot gain curve and densitometre


> Hello everyone,
>
> my wish:
>
> - I still use Piezography with MIS FS on Epson 1160
> - and I still try to obtain by twicking the dot gain curve in PS a
> picture on screen that matches the final print,
>
> and I am not happy with the result... (and think that most of my poor
> prints are due to the fact that I applied inadequate corrections on
> my pictures as shown on screen).
>
> Apperently, I read on the newsgroup that I had to go through a 21
> step wedge print as analyzed by a densotimetre, the reference being
> the X-rite 810 (I have seen a couple exchanged on e-bay for about 200
> to 300 $).
>
> Would someone on the list be kind enough to describe how to work with
> a densitometre (or may be to link me to specific source of
> information)?
>
> Is  the 810 the best product in order to obtain the adequate dot gain
> curve for a correct representation of the print? Do I have also to
> buy the calibration tools for the X-rite 810?
>
> I am ready to spend an another 200/300 $ for having a correct picture
> on screen, but is this densitometre a great deal for such very
> specific job? Is it difficult to work with?
>
> Thanks a lot for your help.
>
Jean-Marc,

A densitometer is a handy piece of equipment to help you calibrate B&W
processing (or color for that matter). If you want to optimize film
development in the traditional Zone System manner it is invaluable.

To use it to obtain a better monitor to print match then you simply use it
to measure the reflective density of a print of a standard step wedge image
on with the ink and on the paper you wish to use. You then need to convert
the density values you record to Dot%. There is an Excel spreadsheet in the
Files section of the group homepage in folder:

Files > Image Processing

Titled: Simple Dot Percent.xls

In the same folder I recommend that you also look at:Matching Your Monitor
view to Your Prints.pdf

This discusses using Custom Dot Gain curves for use with soft proofing which
is the best way to go if you plan to use different curves for different
ink/paper combinations.

You will no get an exact match since a shining monitor and a matte paper
print are so different. A close match is very helpful though but not
strictly necessary to making a good print. Remember that in the darkroom you
had no preview at all. Changes to the printing process were made entirely by
examining the previous print, making adjustments, making another print and
repeating that cycle until you got the print you wanted. To a large extent
the same is still true with digital printing. Especially in fine tuning the
small nuances of a print.

Martin Wesley