Suggestion: make the tail of lowercase L a tiny bit more pronounced.

[nmsmith]

I love Source Sans. It's a great font to use in contexts where legibility is important. I've noticed a small quirk though: in certain contexts, the tail of the letter l is so subtle that it is nearly invisible. In my experience, this is a legibility concern, particularly in contexts where discerning the identity of each letter is important, e.g. when the letter l appears standalone (as demonstrated below), or when it appears in a password or serial number.

I would like to propose that the tail of the letter l be lengthened slightly, so that it is more easily noticed. I've made a mockup below that demonstrates the kind of adjustment I'd like to see.

Source Sans today:

The adjustment I'm proposing:

To more clearly observe the difference between the two images, I suggest opening them both in a new tab and flicking between them.

I'm not specifically proposing the (crude) adjustment pictured in the mockup. The kerning might also need to be tweaked. Anything that makes the tail on the l a bit more pronounced would be fine.

Please let me know what you think.

[pauldhunt]

@nmsmith I will have a look at it, but will make no promises that anything will change. The tail is not so much meant to be noticed as it is to be felt, in particular as a small detail that helps differentiate it from similar letter shapes. Even at the small image sizes you show here, I believe it is doing that job.

[nmsmith]

I understand what you mean, and I believe we want the same aesthetic for the font. My belief that the l is a bit too subtle is drawn from my recent experience using it at small font sizes for both prose and short snippets such as button labels. The issue is more pronounced on low DPI screens. Here's another example:

This is the font at 14px on a low DPI screen. At a glance, I find it hard to tell whether the snippet is Fol or FoI. Here's the latter:

Capital I can be made more distinct by using the character variant with crossbars — and I do use it — but it doesn't help people who are unfamiliar with the font to identify l.

Here's the first image after a bit of oomph has been added to the tail:

I find this tweak makes a big difference.

A more common example is "AI" vs "Al", as in "My best friend is Al" or "a compound of Al and Cl" (aluminium chloride).

Thank you for taking the time to look into this.