Hi Stuart,
I think ligature use is determined more by the type of font in question. I've been working on an antique style handwriting font lately. In handwriting, forms are predominantly connected. Most connections can occur smoothly in the same place. I find that letters whose stroke end at the top such as o v w and sometimes b often work best with ligatures. w_h is one that seems to flow better that way. I don't always make ligatures for double letters as contextual substitution seems to cover that well enough. Exceptions to that are usually combos with crossbars like f_t t_t or things like oo. Sometimes I get tempted into spicing things up a bit and include ligatures that are for beginnings only.

All this is assuming we're talking about Open Type ligatures as opposed to creating a 2nd PS version with extras. If you go too wild with ligatures you have to watch out for conflicts. For instance, if you have both o_o and o_n you might consider an o_o_n ligature to be first in line.
Hope that helps ...not exactly a list.
Stephen

The most useful OpenType ligature or alternate pair is the one that's not included in the typeface :)

The most useful OpenType ligature or alternate pair is the one that’s not included in the typeface

Like f + igrave (or a lot of vowels with a grave, dieresis, breve, caron, etc.).

<---(Formerly blank comment)
(Man, the re-ordering of edits is a pain in the a**)

THAT's your ligatures to build, right there. Replacing swear words with family-friendly alternatives.)

I was speechless.

Speak, Dan---speak. I'm listening. I hear your champagne laff, I live in the curtain, I sleep in your hat ;^)

Hi Stuart---Ray Larabie has made a quite a few OT fonts loaded with discretionary ligatures that may be worth your while checking out:
Mecheria
Sinzano
Zamora
Rinse
Neuzon
Oxeran
Croteau

Neuropol ligatures is one giant ligatures font from the pre-OT era, but the pairings are closely related to the Neuropol structure.

>As for suggestions on novel ligatures, look for combinations where ordinary letters would collide, particularly in the descenders, g_j, g_y, g_g, j_j, and almost anything preceding j.

That's been one of my main uses of ligatures, for collision avoidance, and pairs that normally have poor fit like r_a.

j a m e s

Being that I deal with the ff ligature on a daily basis I have to say it is important. Yeah, I'm vain. If a typeface doesn't have a nice ff lig when it *should* have one I turn the page quickly.

TIC

I see you just considered the source, eh Joel? :-)

ChrisL

Eben, at face value I'd rather trust the designer to give me ligatures that work with the design. However, some fonts have ligatures that are spaced (or drawn however you see it) that are too tight and force the user to either not have control over letter-spacing or turn off ligature usage. But in this instance, I'm thinking of designs that beg for the first letter in the double-f lig (or any double letter lig) to be slightly different than the second.

I really wish to see a text face with a solution for f+umlauts.
In German language, ‘fä’, ‘fö’ and ‘fü’ are anything but rare, just think of ‘für’ [‘for’].
In a lot of classic serif faces the drop of the ‘f’ reaches out quite far to the right. That’s why there are ligatures like fl, ff, fi – to avoid collision, right?

So, dear type designers: before doing fancy things like including ‘ffj’ and ‘ſſl’ ligatures, 5 different ampersands and a truckload of ivies, please consider addressing this umlaut issue!*

See this illustration:

Yellow is (to me) only just acceptable, red isn’t anymore.
And, of course: the bolder, the more clotted it gets.

By the way, I didn’t pick 4 fonts by Adobe because they were especially ‘bad’ – no, this problem is inherent to all faces that have an extensive ‘f’. I used these fonts as they are commonly regarded as being – in all aspects – very well equipped OpenType text fonts – and still suffer from this particular issue.

In my humble opinion, merging the ‘f’ drop with the left dot of the umlaut (as in ‘fi’) can’t be the way to go – that would look really awkward. I’d love to have an alternative ‘f’ with a narrower top for those cases, preferably with automatic substitution, via the lig feature.

And while doing so, don’t forget the triple combinations :°)

I don’t think this problem is limited to German language; the Swedish among others will benefit aswell.

F

*) Don’t get me wrong; I very much appreciate all those special equipment. All I want to say is: first things first.

Not as sophisticated as Adobe, but here is one of the Central European ligs from Chai Tea Pro.
Stephen Rapp

I thought I had with the first sentence. :^) If the type designer thinks that is the best solution then why not. Of course, I'd want to see an example and test it for myself. ;^)

No. I don't see any superiority. As far as I am concerned I want the ligatures to belong to the design. I suppose the only reason I might think the one glyph model would be superior is because the design calls for true integration of the shapes.

Aha! I thought I heard something rattling around. ;-)

But what if prior to any tracking going on you could have uterly identical shapes? Admittedly it might be that some kinds of designs wouldn't be amenable to this - but just for the sake of argument - if you could get a lig that was visually identical - then I think the reason for 1 glyph ligs evaporates.* Do you agree? Feel free not to!

With one important exception: Backwards Unicode compatibility. But you could include a glyph with out using it in your replace functions!

Sorry. I didn't realize how opaque some of this was. I will do my best.

In the case of backwards compatibility I am saying that a text can be hard-encoded to include the glyph for ff or fi for instance. And if you had a text like that you could loose the meaning of the text if you didn't include the single unicode glyphs 'ff' or 'fi' in your font.

On the other hand, if you had a common sort of text - the sort we set 99.9 % of the time - with fand i or fandf indicated as separate glyphs you could allow the ff & fi to interpreted into the visual appearance/shape of a classic ff or fi ligature but using coding to make two glyphs overlap.

And as far as why you would want to - a regular one glyph ligature often looks quite wrong with only fairly minor tracking.

So.. one solution to that ( apart from not tracking a font ) is that as a font designer you could contrive a design that let the shapes ( within a tight range probably ) to flex in tracking right along with the other letters. Then inter letter spacing wold be consistent.

Probably the best thing to do is to make a visual reference! I have been meaning to make a stab at one for some time in order to see what results were possible. And to see what the practical limitations might be.

Of course not everybody uses InD... ;-)

But still that's a good point. On the other hand if the font is well made it might be better left with it's own kerning table.

James; what's your take on this? Does what I am talking about make sense to you?

A minor point - those ct & st ligs might not survive my plan, depending on how they were made.

I think the idea of coding to overlap the letters accordingly sounds dangerous. Interesting, but dangerous. I can imagine what you're talking about, but the proof would be in the pudding, so to speak. Show me what you're thinking, let's see if it is possible.

Florian, MUFI fonts have fä, fö and fü ligatures. They use the solution you reject as awkward, but considering the nature of the project I must assume there is historical precedent for the form.

Kevin, thanks for the link!
I decided to start a new thread on the ‘f’+umlaut thing, as this is quite special, and I don’t want the question get buried by other aspects.
F

Good idea Florian!

Paul, I have been looking at some examples that would probably not work as given. They would have to be re-invented to a certain extent. I am looking forward to comparing solutions.

Carlos,
yes, see the spin-off thread: f + umlauts.
Note however that most commentators (including myself) feel it is better to have a contextual alternate (a short f), than to introduce uncommon and potentially annoying ligatures.

of course totally agree with your remark. fï ligs are weird in Ingeborg.
After reading the thread you created Florian, I conclude that merging the f's drops with the first umlaut's drops gives the f too height in comparison of the 'standard' f. It's like an arm that tries to catch an object (ball) out of reach !

.

.
You never come at an end …
(Is there really a use for f_f_f??)

schifffahrt

No!! This is a compound word: Schiff-fahrt. An established rule says that you must not use any ligature across word boundaries.
Apart from that, Schiffahrt with 3 f’s is dull new age spelling, no decent German.
But that’s another thread ;-)