+@node Engraving
+@section Engraving
+
+The art of music typography is called @emph{(plate) engraving}. The
+term derives from the traditional process of music printing. Just a
+few decades ago, sheet music was made by cutting and stamping the
+music into a zinc or pewter plate in mirror image. The plate would be
+inked, the depressions caused by the cutting and stamping would hold
+ink. An image was formed by pressing paper to the plate. The
+stamping and cutting was completely done by hand. Making a correction
+was cumbersome, if possible at all, so the engraving had to be perfect
+in one go. Engraving was a highly specialized skill; a craftsman had
+to complete around five years of training before earning the title of
+master engraver, and another five years of experience were
+necessary to become truly skilled.
+
+Nowadays, all newly printed music is produced with computers. This
+has obvious advantages; prints are cheaper to make, and editorial work
+can be delivered by email. Unfortunately, the pervasive use of
+computers has also decreased the graphical quality of scores.
+Computer printouts have a bland, mechanical look, which makes them
+unpleasant to play from.
+
+
+@c introduce illustrating aspects of engraving, font...
+The images below illustrate the difference between traditional
+engraving and typical computer output, and the third picture shows how
+LilyPond mimics the traditional look. The left picture shows a scan
+of a flat symbol from an edition published in 2000. The center
+depicts a symbol from a hand-engraved B@"{a}renreiter edition of the
+same music. The left scan illustrates typical flaws of computer
+print: the staff lines are thin, the weight of the flat symbol matches
+the light lines and it has a straight layout with sharp corners. By
+contrast, the B@"{a}renreiter flat has a bold, almost voluptuous
+rounded look. Our flat symbol is designed after, among others, this
+one. It is rounded, and its weight harmonizes with the thickness of
+our staff lines, which are also much thicker than lines in the
+computer edition.
+
+@multitable @columnfractions .125 .25 .25 .25 .125
+@item @tab
+@ifnotinfo
+@iftex
+@image{henle-flat-gray,,4cm}
+@end iftex
+@ifnottex
+@image{henle-flat-gray,,,png}
+@end ifnottex
+
+@tab
+@iftex
+@image{baer-flat-gray,,4cm}
+@end iftex
+@ifnottex
+@image{baer-flat-gray,,,png}
+@end ifnottex
+
+@tab
+@iftex
+@image{lily-flat-bw,,4cm}
+@end iftex
+@ifnottex
+@image{lily-flat-bw,,,png}
+@end ifnottex
+@end ifnotinfo
+@ifinfo
+@c workaround for makeinfo-4.6: line breaks and multi-column cookies
+@image{henle-flat-bw,,,png} @image{baer-flat-bw,,,png}
+@image{lily-flat-bw,,,png}
+@end ifinfo
+
+@item @tab
+Henle (2000)
+@tab
+B@"{a}renreiter (1950)
+@tab
+LilyPond Feta font (2003)
+
+@end multitable
+
+
+@cindex musical symbols
+@cindex font
+@cindex blackness
+@cindex balance
+
+@c introduce illustrating aspects of engraving, spacing...
+In spacing, the distribution of space should reflect the durations
+between notes. However, many modern scores adhere to the durations
+with mathematical precision, which leads to poor results. In the
+next example a motive is printed twice. It is printed once using
+exact mathematical spacing, and once with corrections. Can you
+spot which fragment is which?
+
+@cindex optical spacing
+@c file spacing-optical.
+@c need to include it here, because we want two images.
+@lilypond
+\paper {
+ ragged-right = ##t
+ indent = #0.0
+}
+
+music = {
+ c'4 e''4 e'4 b'4 |
+ \stemDown
+ b'8[ e'' a' e'']
+ \stemNeutral
+ e'8[ e'8 e'8 e'8]
+}
+
+\score
+{
+ \music
+ \layout {
+ \context {
+ \Staff
+ \override NoteSpacing #'stem-spacing-correction = #0.6
+ }
+ }
+}
+@end lilypond
+
+@lilypond
+\paper {
+ ragged-right = ##t
+ indent = #0.0
+}
+
+music = {
+ c'4 e''4 e'4 b'4 |
+ \stemDown
+ b'8[ e'' a' e'']
+ \stemNeutral
+ e'8[ e'8 e'8 e'8]
+}
+\score
+{
+ \music
+ \layout {
+ \context {
+ \Staff
+ \override NoteSpacing #'stem-spacing-correction = #0.0
+ \override NoteSpacing #'same-direction-correction = #0.0
+ \override StaffSpacing #'stem-spacing-correction = #0.0
+ }
+ }
+}
+@end lilypond
+
+@cindex regular rhythms
+@cindex regular spacing
+
+Each bar in the fragment only uses notes that are played in a
+constant rhythm. The spacing should reflect that. Unfortunately, the
+eye deceives us a little; not only does it notice the distance between
+note heads, it also takes into account the distance between
+consecutive stems. As a result, the notes of an up-stem/@/down-stem
+combination should be put farther apart, and the notes of a
+down-stem/@/up-stem
+combination should be put closer together, all depending on the
+combined vertical positions of the notes. The upper two measures are
+printed with this correction, the lower two measures without, forming
+down-stem/@/up-stem clumps of notes.