Re: PostScript Files

From: Jim Wood (electrojim_at_sbcglobal.net)
Date: 02/12/04 

Date: Wed, 11 Feb 2004 17:35:42 -0800

Mac,

     Many thanks for a most thorough explanation. You not
only provided an answer to my question, but informed me of
the "why" as well. That's important, as it's one thing to
know _what_ to do, but _why_ completes the understanding.
     I require a positive film for silkscreening the front
panels of my company's products. I've been using
Publisher for this: 1) it works well enough for what I
need to do; 2) I've learned Publisher and have become
sufficiently proficient in it; 3) It came free with my
computer, which is better than paying several hundred for
Adobe Illustrator, probably the ideal program for what I
need to do, except that I would have to learn it.
     We used to be able to send Publisher files to a local
service bureau and get film. No longer. Now they farm
their film work out to a third party. Printers all
go 'direct from digital,' whereas silkscreeners still need
a film positive.
     I need to hold a ±0.01 inch tolerance across a 19-
inch-wide panel. I'm afraid that in using a PDF file
(which I am given to understand can't be manipulated by
the filmmaker), the tolerance can't be held. I don't know
what sort of photosetter he might be using, but don't
imagine that he can take my 19-inch registration marks in
the digital file and shrink or grow the film by a fraction
of a percent to nurse it in. As you seem the resident
expert on this, can you tell me if this is possible?
     I used the driver for the Agfa AccuSet that our
service bureau used to use, and was able to create a
PostScript file. From there, Acrobat Distiller gave me a
nice-looking PDF... much nicer and a much smaller file
than Publisher created directly using PDF Writer. In
fact, I have an e-mail with some images of what I got both
ways if you would be interested.
     Where is your service bureau? I'm in California, but
finding a knowledgeable filmmaker, either near our factory
in the Bay Area or near the office where I am, not far
from L.A., is proving difficult.
     Again, many thanks for your in-depth description of
the process!

Jim Wood
Brea, CA

>-----Original Message-----
>Sounds like you already have Acrobat Distiller.
>
>There's your PostScript printer.
>
>Let me back up a moment and try to describe the
difference between a
>PostScript printer and the "others". I appologize if this
comes across as "I
>asked a simple question and he gives me a paegent" but I
believe an
>understanding of the nature of the thing is important.
>
>About 20 years ago PostScript solved the problem of how
do we get what we
>see on the screen onto paper pretty much just like we see
it. (and without
>PostScript, Apple Computer might not exist today because
the Apple
>Laserwriter and PS pretty much saved their bacon at that
time)
>
>PostScript is a page description language...a programming
language that is
>optimized for describing things that can appear on a page
such as type and
>pictures. One could write an accounting program using
PostScript, but it
>would be easier and better to use something else.
>
>When you print to a PostScript printer the printer driver
(using information
>gleaned from the PPD--"PostScript Printer Description")
sends a stream of
>PostScript codes to the printer. Inside the printer an
interpreter reads the
>incoming data and uses it to reconstruct the page in
memory and then prints
>it out.
>
>If driving a laser printer were all that mattered,
PostScript would be in
>the dustbin of history because clever programmers have
come up with other
>Page Description Languages that work pretty well and they
don't have to pay
>royalties to Adobe for the privilege..,
>
>But Desktop printers are not all that matters. The entire
printing industry
>relies on PostScript and upon complex devices that use
PostScript to produce
>virtually every printed (off a printing press) piece of
paper you see today.
>Your daily newspaper, magazines, brochures, etc.--all
these products are
>produced using PostScript language and devices.
>
>That's the biggest difference between PostScript and non-
PostScript. An
>Epson printer driver will work only for that model of
Epson printer. But a
>postscript file can be made to work on almost any
printer, via Acrobat and
>PDF.
>
>Then the PDF file format and Acrobat were introduced
about 14-15 years ago
>the objective was to take PostScript to a new level and
allow anyone to (a)
>create a document in any program and (b) process it thru
PostScript and
>Distiller to (c) produce a document that looked exactly
like the original
>but that could be viewed on virtually any computer
anywhere and printed to
>virtually any printer connected to that "anywhere"
computer....all without
>having to also distribure the creating software.
>
>The mission of PDF has changed somewhat in the past 15
years. Today it is
>also (for many) a preferred prepress format...meaning
that you can hand off
>a properly prepared PDF file to a print shop and they or
their service
>bureau (I am a service bureau) can then generate to film
or printing plates
>needed to put the job on-press.
>
>To get a PDF you need a PostScript file. An Epson or HP
driver won't do the
>job.
>
>Now...on to your question.
>
>It sounds like you have Acrobat 4 installed, because you
reference PDF
>Writer.
>
>PDF Writer was an attempt by Adobe, since abandoned, to
generate PDF without
>first creating PostScript. PDF made by this route seem to
look fine and work
>ok for the original idea of "this is what the document
looks like--kinda
>sorta" but since it does not properly handle the fonts
and degrades images,
>PDF made via PDF Writer are totally unacceptable in the
prepress
>envirnonment and enough of them made it there and the
hollaring was loud
>enough that Adobe pulled the plug on the idea. Bottom
line, don't use PDF
>writer.
>
>Adobe also tried something called the DA or Distiller
Assistant which
>attempts to hide the creation process by seeming to print
directly to a PDF.
>In fact when you print to Distiller it makes a postscript
file then it opens
>distiller and then it feeds that postscript file to
distiller and then it
>drops that pdf file not where you can easily find it, but
somewhere in
>C:\Program Files\Adobe\Acrobat x\Distillr\xxx.
>
>PDF so created have an excellent chance of being prepress
ready (which is
>what you need in order to get film output). BUT there is
another step you
>MUST make. Distiller has a huge number of settings and
many of these are
>inappropriate for the use you want. These settings are
all boiled down into
>a set of "job options" which make it easy for you.
>
>Open Distiller and you will see a listbox titled Job
Options. scroll thru
>that list until you see one called "Press". That's the
one you want. For
>emailing stuff that's NOT to be used for prepress, then
try one of the other
>options...but do not expect PDF made with one of the
other options to work
>eiterh at all or as well as one made with the press job
option. They guy
>making the film may have his oen job option he would
prefer you to use and
>if so, he can tell you where to put it (C:\Program
Files\Adobe\Acrobat
>x\Distillr\settings) and his version will then appear in
the list box in
>Distiller.
>
>You are done.
>
>If the autmatic process causes problems, and sometimes it
does (I don't use
>it myself) you can change the behavior.
>
>1) In printer control panel, select Distiller, right
mouse button,
>properties. Ports tab. change the checked box to "FILE"
and save/ok your way
>out of the properties boxes.
>
>2) now when you print to distiller it will ask you for a
file name.
>Depending on your operating sustem, it may be a simple
box wherein you must
>type the whole path and filename including extension. I
dont' like to type
>that much, so I have a folder i use all the time so i
would type in
>"D:\output\file.prn" or "D:\output\file.ps" (there's no
real difference in
>this case between the .prn extension and .ps). This
creates a PostScript
>file in the output folder on drive D.
>
>A PostScript file is usually pretty big. You can then
make a PDF from it.
>
>3) open Distiller and make certain you have the correct
job options listed
>in the window. Then Either (a) use Windows Explorer to
find the PostScript
>file you made and drag it to and drop it on the Distiller
window. Distiller
>will than make the pdf and put it in the same place the
PostScript file came
>from (in this case, D:\output). OR (b) with Ditiller
open, go to the FIle
>Manu, Open and navigate to where the PostScript file is
located. If you used
>the "prn" extension you may have to go to the "files of
type" list and
>change it from "PostScript files (*.ps)" to "All files"
for it to see the
>..prn--this is not necessary if you use the drag and drop
method.
>
>That should about cover it. I hope<G>
>
>
>
>.
>