Loading ...
Sorry, an error occurred while loading the content.

RE: [PPLetterpress] PostScript printers

Expand Messages
  • Michael Andrews
    Hi Converting from filetypes to TIF in order to flatten a postscript will, at best be only adequate, and in some cases adequate only for screen resolutions.
    Message 1 of 5 , May 10, 2005

      Converting from filetypes to TIF in order to flatten a
      postscript will, at best be only adequate, and in some
      cases adequate only for screen resolutions. It is
      very like flattening a type layer in Photoshop. Better
      than nothing, but only just.

      It is only partially effective in emulating what a RIP
      or a postscript chip can do for a specific printer.



      --- "Ludwig M. Solzen" <ppletterpress@...>

      > I hope the moderator will agree that this issue is
      > not off-topic at all. The
      > RIP (rasterisation) forms the most essential link
      > between digital prepress
      > and press (apart from the production of appropriate
      > photopolymer plates, of
      > course).
      > As far as I understood PostScript is a form
      > description language, by which
      > shapes are described 'mathematically'. Although not
      > the single one ever
      > designed, PostScript has gained the commercial
      > monopoly because its
      > developers at Adobe Systems Inc played the market
      > game better than their
      > competitors. Like other form description languages,
      > PostScript uses Bezier
      > mathematics to describe straight lines and curves,
      > and so in different
      > degrees (going from splines to nerbs &c). To render
      > shapes, whether that be
      > on screen or on paper (in the latter case by use of
      > a printer or film
      > setter), the arithmetic descriptions must be
      > translated into a map of dots:
      > a so-called bitmap. Such a map consists out of a
      > grid of squares that may be
      > black or white, 1 or 0. According to the relative
      > number of squares per
      > absolute surface, the shapes rendered on the grid
      > will hold more or less
      > detail. On screen there are usually only 72 dots
      > (squares) for every inch; a
      > regular laser printer will cope with at least 300
      > dots per inch (or DPI).
      > Now, my Epson AcuLaser C1900 is claimed to have a
      > resolution of 600 dpi.
      > However, I notice that if I try to print a text, set
      > in Bodoni (a PostScript
      > font indeed!), 6 points, the serifs get lost, the
      > lowercase o cut through
      > and so on. Are these faults to be explained by the
      > inapt resolution of my
      > excellent laser printer? Should I invest in an over
      > expensive 3200 dpi
      > Linotronic film setter? I don't think so - 600 dpi
      > is good enough, since I'm
      > fond of printing on rough surfaced papers, where
      > resolutions higher than
      > that are wasted. So, what is the problem with my
      > Bodoni 6 pts? This is what
      > I think. My AcuLaser translates my layout postscript
      > files not adequately to
      > its 600 dpi grid of blackened or left open squares.
      > This problem has a name:
      > 'hinting'. Perfectly vertical or perfectly
      > horizontal straight lines do not
      > form a problem: on the grid they will be translated
      > into a consecutive pile
      > of blackened squares. The problem is in the curves,
      > notably when they are
      > exceedingly fine, as in the hairlines of my Bodoni.
      > If a curve crosses
      > diagonally the bitmap grid, the translating software
      > should decide which
      > squares are to be filled in, and which not. If the
      > grid holds too low a
      > number of squares (low resolution), these decisions
      > are challenged
      > extremely. Somehow the translation must be helped in
      > an intelligent way. As
      > for fonts, this intelligence can be in the font file
      > itself ('auto hinting'
      > in truetype), but as for my other vector images, the
      > intelligence must come
      > from elsewhere. I'm said I could buy the
      > interpreting intelligence that
      > translates between my postscript input files and my
      > printed output bitmap
      > raster. It's a piece of hardware that usually comes
      > with the expensive
      > so-called PostScript printers, but is optional on
      > most desktop printers. But
      > maybe there is another, cheaper solution.
      > But I too have a question, since I'm afraid my
      > budget will not allow soon
      > for the acquisition of a Linotronic or even a
      > PostScript chip for my
      > AcuLaser. Am I mistaken, or am I right that instead
      > of sending my layout
      > files directly to the printer, that I could load
      > them in a bitmap image
      > editor, let's say Adobe PhotoShop? If an .eps, .ps
      > or .pdf file is converted
      > into a .tiff bitmap, I presume the software must
      > somehow make a RIP
      > translation from splines into dots. May I assume as
      > well that Adobe PS will
      > do the job probably better than the driver of my
      > Epson printer? And could I
      > expect that if my pages are converted in this way,
      > that my Bodoni 6 pt text
      > will print excellent on my poor little 600 dpi
      > machine?
      > Ludwig
      > [Non-text portions of this message have been
      > removed]
      > ------------------------ Yahoo! Groups Sponsor
      > --------------------~-->
      > What would our lives be like without music, dance,
      > and theater?
      > Donate or volunteer in the arts today at Network for
      > Good!
      > Yahoo! Groups Links
      > PPLetterpress-unsubscribe@yahoogroups.com

      Do you Yahoo!?
      Make Yahoo! your home page
    Your message has been successfully submitted and would be delivered to recipients shortly.