Point (typography)
The terms font, Schriftsatzmaß or cone height (including cone thickness) call in typography, a measure of the size of a font. The cone (picture # 6) is the body which carries the slightly smaller, mirror- image of the letter (# 2) in the lead sentence. The cone height ( distance d ) denotes the height of the lead cone. Since the cones are slightly higher than the letters that cone height or the font size is always greater than the sum of upper, middle and lower length and thus greater than the actual font size.
For the font size different units are used and commonly referred to as " item". These units are used in printing products not only for the font size, but also for line spacing and the like.
Written hard are the dimensions in DIN 16507-1 (current as of September 1998).
The meter for to be entered in dot sizes is the Typometer.
- 3.1 Overview of the typographical measurement system
Optical font size
The picture shows the Helvetica, Garamond and Bickham Script fonts with the same font size in comparison.
Since the font size only the height of the cone describes (even with fonts), he says nothing about the visual appearance of the font size. This depends mainly on the x-height of the font. Does the document, a particularly small upper and lower length, the center length on the font is proportionally larger, as the type designer usually recorded with the span between the upper and lower length of the entire height of the cone.
Script fonts with particularly extravagant upper and lower lengths (such as the Bickham Script) therefore often act very small. For the same reason, the assumption roman typefaces saw generally smaller than sans serif fonts, wrong. This applies only to the comparison of classical Antiqua (like Garamond ) with classic grotesques (like Helvetica ), or of Antiqua and grotesque with a comparable metric.
The units of the system of measurement
The French point system
The point ( p) is the basic unit for specifying font sizes.
The first typographic point system was designed by Sébastien Truchet ( 1657-1729 ). His point was exactly 1/1728 " pied du Roi " (feet), or about 0.188 mm and thus corresponds to exactly half of the later Didot point.
Pierre Simon Fournier, the French printer using its own typographic point since about 1737. He was about 0.345 mm, ie about eleven twelfths later Didotpunkte. The so-called Fournier point was not used.
Was further developed the system of units end of the 18th century by François Ambroise Didot and his son Firmin Didot.
The Didot point, which then also practically prevailed throughout Europe, traditionally amounted to 0.376065 mm (official translation but about 0.3759715 mm). It is usually given as 0,376 mm and also as used ( with 0.0173 % and -0.0075 %, well within all technical tolerances). The basic measure was the foot, the old French measure of length Pied de roi. So given 6 × 12 × 12 = 864 Didotpunkte exactly one French foot.
1975 has been proposed to round the Didotpunkt to 0.375 mm. However, for use with the existing presses a modification of more than one quarter of a percentage significantly and was therefore technically difficult to realize. It was also just changed at this time phototypesetting technology that uses the DTP point. Thus, this proposal was never fully implemented in practice, although often simplistic a Didot point than 3 /8 mm is specified.
The next largest unit in this system is the Cicero. A Cicero equivalent to 12 Didot points. Four Cicero, in turn, result in a concordance.
The American point system
End of the 19th century came from the USA with the invention of the Linotype- line casting machine an alternative point measure to Europe: the Pica - point (pp). Used its own American " printer stand ", which quite accurately corresponds to 1024/1000 Roman feet, or about 303.5 mm The American printer.
From three competing, almost same definitions the 15th Meeting of the U.S. Association of the USA Type Founders adopted (1886 ) the so-called " Johnson Pica " to exactly 0.166 inch. The other two proposals, Nelson C. Hawks: 1200/7227 equal to about 0.166044 inch, and the direct reference to the metric system: 83 pica in 350 mm, or about 0.1660184 inches were not considered.
Therefore, the traditional American Printer 's Point measure 0.35136 mm. Analogous to the Didot point here is a Pica ( = 0.166 inch) the next higher font metrics of 12 points.
DTP -point system
The DTP point system (DTP by: Desktop Publishing) is used in the IT sector almost exclusively today.
Typographical DTP point, abbreviated pt ' ( TeX, bp ' for big point (big because it is slightly larger than the above-mentioned Printer 's Point ) ), sometimes also called PostScript point, was ranked as the 864th part of the English compromise foot of 1959 defined. It also measures exactly 1 /72 inch, that is, 0.0138 inch or 0.3527 mm. He is currently the only reliable measure in most application programs ( printer communication, Word, Photoshop, etc. - CorelDraw, however, was programmed metric ).
In a frequently encountered in the print dot density of 300 dpi, a DTP point then corresponds to about four pixels in the reproduction. A character with 12 pt is printed in height under these conditions with 50 points.
DIN 16507
The German standard DIN 16507-2:1999 looks for font size and line height information in the electronic record has a modulus of 250 microns before, with a submodule of 50 microns for intermediate sizes. This module is also partly as a corresponding point unit used and is then called Quart (, q ' ), since it corresponds to a quarter of a millimeter.
Instead of the cone height, the measurable size of the cap height is used to specify the font size in DIN 16507-2. This system has so far not been widely distributed, however, support a variety of computer typography languages (eg TeX, CSS, FrameMaker ), the values are in metric units.
Otl Aicher was one of the proponents of this system and propagated font sizes, which are partly inspired by the traditional name.
Relative sizes
In addition to absolute font sizes in which a font size a certain length can be assigned, there are in computer graphics and a values are in pixels ( px). While the real size of a pixel is determined by the structure with devices that may occur when printing a font size specified in pixels to surprises when the association is not fixed. Therefore, a conversion into DTP of 1 inch = 72 pt = is set 96 pixels for example, in CSS for pixel values . Thus, the relative font size is assigned an absolute font size. Other defined in CSS units like ' em ' and ' ex' refer to the current font and are therefore normalized only with establishing an absolute font size.
Table of font sizes
The corresponding DTP sizes are fairly accurate one-sixteenth smaller than the Didot - dimensions.
Overview of the typographical measurement system
From a font size of 4 point, the " German normal baseline " applies. The distinction "Gross " in front of the font name often indicates a reduction in the baseline to accommodate a slightly larger ( coarser ) typeface on the same high cone.
The font sizes in other European countries sometimes had different names, same or similar names were for other font sizes. From the " canon" (36 point) upward indicated even in Germany the names are not always the same font. Thus one finds " canon" for 32 and 36 points, " Rough gun " for 40 and 42 point, " Missal " even for 48, 54 and 60 points. " Sabon " and names were always greater extent for different cone heights.
The table shows the most common names stand first.