Re: metafont modes

["Nelson H. F. Beebe" <beebe@csc-sun.math.utah.edu>]

>> My printer is a  HP laserjet 6L, and there
>> is no mode for it in the version of modes.mf which I have.

>> Am I supposed to use "ljfive"?  What is the best choice for me?
>> How can I obtain the most recent version of modes.mf?

The last release that I have installed here is modes.mf 3.2, dated 

	Thu Nov 7 15:51:45 EST 1996

Karl Berry maintains that file, and announces new versions on this
list, and possibly other lists.  The CTAN archives (finger
ctan@ftp.tex.ac.uk for a list) should have the new version within a
few days of announcement.

You can very likely use ljfive, ljfivemp, or ljfour with acceptable
results.  Remember that many laser printer vendors use the same
engines (Canon and Ricoh are major manufacturers of such).  We have 28
printers in my department, from several different manufacturers
(Apple, Hewlett-Packard, Imagen, Lexmark, ...), and not once have I
received a complaint about font quality arising from our use of ljfour
as the standard mode on all of these models.  Remember that users will
often generate a PostScript file from a DVI file, then print it
anywhere, or post it on the Web for printing at other sites.  Thus,
one cannot realistically expect the Metafont mode chosen to routinely
match the printer finally used.

The biggest difference in laser printer engines is white-writing
versus black-writing (start with a black background and remove dots
leaving letters shapes behind, or start with a white background and
add dots to create letter shapes).  

Several Xerox and Ricoh engines are white-writing, and all Canon
engines I know of are black-writing.  Between these two classes, there
can be significant differences in appearance: black-writing engine
fonts on a white-writing engine usually look rather thin, and under
magnification, the cause is evident.  White-writing fonts on a
black-writing engine will likely appear to dark.  And don't forget
individual printer density adjustments: earlier this week, I
investigated a complaint about light output from one of our lab
printers, and found that someone had reduced the toner intensity
adjustment buried deep inside the printer.

If you are really concerned about achieving the best appearance of
your fonts, you might consider using outline fonts instead of bitmap
fonts.  There are two sets of Computer Modern fonts, the BaKoMa fonts,
and the BlueSky/AMS fonts, both in the CTAN archives.  The latter have
had thousands of hours of work in hand tuning.  However, I've used the
BaKoMa fonts quite happily for some time (their release predated the
other by a couple of years).  

By leaving the rasterization job until the file is inside the printer,
you are more likely to get printer-tuned optimal appearance of fonts.
The drawback is the larger size of such files (perhaps a factor of
two, unless the driver supports font subsetting).

There is a big payoff, however, if you want to convert them to PDF for
viewing on the Web: the current versions (1, 2, 3) of Adobe Acrobat
Reader do an abysmal job of displaying bitmap fonts, and a very good
job of displaying outline fonts.  Thus, I always recommend use of
outline fonts for preparation of PDF files.  Perhaps I can find some
time to put up some examples of the two cases.

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- Nelson H. F. Beebe                  Tel: +1 801 581 5254                 -
- Center for Scientific Computing     FAX: +1 801 581 4148                 -
- University of Utah                  Internet e-mail: beebe@math.utah.edu -
- Department of Mathematics, 105 JWB                   beebe@acm.org       -
- 155 S 1400 E RM 233                                  beebe@ieee.org      -
- Salt Lake City, UT 84112-0090, USA  URL: http://www.math.utah.edu/~beebe - 
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