Why are italics lighter than their upright counterparts?

Wei Huang
Wei Huang Posts: 97
edited September 2015 in Technique and Theory
I think there was a thread on Typophile about drawing Italics but… obviously I can't find it. I have a a question I hope someone can shed some light on:

Why are Italics usually lighter than their roman counterparts? How is this calculated, or decided how much it should be lighter by?

Checking the outlines themselves, the stems are actually drawn lighter than the upright too. In text its clear that that italics are lighter too. Is it so that the italics don't stick out in running upright text and that these typefaces were not designed with running italics text next to upright in mind?

(While I'm here does anyone have the link to the thread on Typophile [to access on Archive.org] where David Berlow or someone else from Font Bureau explains how they create a slanted sans?)



  • James Puckett
    Two reasons. Italic stems, being angled, have to be drawn slightly lighter or they look too dark. But they're often drawn to produce a lighter color than a roman so that they stand out when used as a hierarchical device in text.
  • Italic x-heights can also be made slightly lower to compensate for the angled stems being longer. 
  • Max Phillips
    Also: italics are often narrower (at least the lower case), than their corresponding romans, which means the stems must be proportionally narrower, too.
  • Choz Cunningham
    Choz Cunningham Posts: 18
    edited September 2015
    Italics were used to save space (and paper) by Francesco da Bologna . I assume, to compensate for being narrower and more tightly tracked, the developer felt they needed lightening, less they darken the page too much.

    Obliques are often share their upright brethren's weight and tracking, and are usually very close in weight; that just might be because they are computer tilted knock-offs, though.
  • Jan Tonellato
    Indeed, if it was only to compensate the width or the angle, we shouldn't notice they're lighter in body text. It's also strange to say, today, the italic has to be lighter to stand out as we should consider a lighter style as we so with uprights. Maybe the reason is mostly historical? Something about too-much-ink when printing?
  • Ray Larabie
    After from using alternate italic forms, when I make sans-serif obliques, slanting alone creates an italic that usually fails to sufficiently emphasize. Although, I could keep increasing the angle, at a certain point, it starts to look ridiculous. The slant is just one aspect of an oblique. Lighter stems, condensing, looser sidebearings...all that stuff helps.
  • Wes Adams
    Wes Adams Posts: 59
    edited September 2015
    @Choz, I've frequently heard that Manutius found Griffo's italic to be laterally compressed and have never seen any evidence that it actually is... or that it was ever Griffo's intention in cutting it. As its progenitor, its equally possible that he followed the much admired Roman chancery hand and that efficiency was a byproduct of the model.

    A bit of a tangent I suppose, Manutius's italic-set books usually contain no roman at all and it wasn't really until Granjon that the italics acquired a greater slant, a lighter weight, and more compression. By that time setting roman and italic together was fairly common.
  • Michael Jarboe
    Slanting an upright stem without adjusting its stem thickness at all still creates the optical appearance that the slanted stem is lighter.

    It's design-dependent, but sometimes a reduction in width is not necessary, the italics/obliques will naturally look lighter.

    It's the same reason that in already angled stems (such as A), slanting makes this optical discrepancy even more pronounced. After slanting the upstroke will appear lighter, while the downstroke darker.

    With some basic sans designs, I've found that the italics/obliques without any stem width reduction, still look lighter next to the romans because of this.
  • Wei Huang
    Wei Huang Posts: 97
    edited September 2015
    What I gather from this discussion so far:

    Merely slanting an upright makes the font look too dark. Therefore it is made lighter to compensate. This I understand.

    But most of the serif designs I see take it further and actually reduce the weight so that optically they appear even lighter than the uprights. This is done is so that the italic has enough emphasis (like a word within a line or a sentence within a paragraph?) compared to the upright text —why not have italics that are darker instead?
  • Michael Rafailyk
    Michael Rafailyk Posts: 143
    edited November 2021
    Thinking about Italic stem width, I also think about the diagonals in the letters A, N, V in roman style, which are also should be narrower than the vertical stems. I think the same rule is applies to italic, as the first step of adjusting. The reason is that we read horizontally and perceive the total mass falling into the reading direction.

  • Thomas Phinney
    Another reason why italics are lighter is probably that humanist roman scripts are being written with a pen held at approx. 30°, whereas humanist cursive scripts are typically written wit a pen angle of 45°. When you write these scripts with the same pen at the same x-height, the cursive script is always lighter than its roman counterpart.

    Adam’s version is a great post-hoc rationalization, yet… this makes a lot of sense to me, as regards the most likely historical origin of the difference in italic stroke weight.

    To expand on what AJP is saying here: the larger the difference between nib angle and stroke direction, the thicker the stroke.

    Writing a vertical stroke with a 30° nib angle, there is a 60° difference between nib angle and stroke direction. Writing a 10–20° italic with a 45° nib angle, there is a 25–35° difference between the nib angle and the stroke direction, for the nominally-vertical strokes.

    Yes, both forms have some strokes that are at an equal maximum thickness. But the most common stroke thickness is the vertical (or “nominally vertical” in the case of the italic), and the impact on the most common stroke makes for a significant difference.
  • Chris Lozos
    Chris Lozos Posts: 1,458
    as long as the type designer is making it what he wants it to be instead of letting it  be whatever happens without control, it is fine with me.

  • John Hudson
    John Hudson Posts: 3,013
    Is it begging the question to say it is due to nib angle? There are reasons why scribes hold and manipulate pens in different ways for different script styles. In the case of italic hand, it seems to be two-fold: a) the steeper angle of the nib lends itself more to cursive construction, facilitating reversal into NE direction strokes, and b) the horizontal compression that comes from the speed of italic writing makes the spatial frequency of strokes denser than roman, so the lighter weight of the strokes compensates.
  • Whatever the type designer wants to do, Italic should stand out if mixed with Regular, or it can't be used. IMHO in this example of a "Swiss" monoline it's hard to recognise for fast readers:

    In comparison Garamond takes the contrast between Regular and Italic to an extreme:

  • Craig Eliason
    Because it came out after this thread's first life, but before it was revived, I'll drop a reference here to Victor Gaultney's work on the italic topic
  • Russell McGorman
    Because it came out after this thread's first life, but before it was revived, I'll drop a reference here to Victor Gaultney's work on the italic topic
    Thanks for sharing that, Craig.