[comp.text.tex] Question: kerning of "oj", "bj", "pj" and "aj"

kimura@opdgw.strg.sony.co.jp (Tetsu Kimura) (06/24/91)

Dear TeXnicians,

I once asked about this quetion in domestic network but
could not get an answer. So I decided to ask here.

It's about kerning of the Computer Modern Font.
I have installed Japanese version of TeX (it is based on tex2.99)
4 month ago. One user complained about the printout of the word
"Project".  He said, "I feel the space between 'o' and 'j' is
too wide." Well, I hadn't noticed until then, but I felt in
the same way. So I looked into the definition of the font
and found following description in the tex2.99/cmfonts/mf/roman.mf

 ligtable "o": "b": "p": "e" kern -k#, "o" kern -k#, "x" kern k#,
   "d" kern -k#, "c" kern -k#, "q" kern -k#,
  "a": if serifs: "v" kern k#, "j" kern u#, else: "r" kern k#, fi
                               ^^^^^^^^^^^
This means, if it is serif-font, insert kern to widen the space
between "oj", "bj", "pj" and "aj". We feel rather shrinking the
space makes the word more beautiful. We have tested several kering
values and found

	"j" kern k#

makes a good result.

Question: Is the original kern is correct? (Is there any rule
	  to widen the space in type setting?) Or Is it a bug and
	  kern k# is correct? (It's hard to believe ...)

Please reply by e-mail if possible.
Thanks in advance.

------------
Tetsu Kimura			e-mail: kimura@strg.sony.co.jp
Sony Corporation
2255 Okata, Atsugi-shi
Kanagawa, Japan