Hello! I am a bit of a lurker on TypeDrawers, but I thought I'd try to make my first post.
I have a question about foot serifs that are cupped, as in the sample image below.
I have read several different reasons:
1) In Sofie Beier's book "Type Tricks" (which I think is quite helpful) and in this article
by Mark Jamra, both authors note that an optional illusion can occur where serifs appear to bend outward. This illusion is corrected by cupping the serifs. However, I have never really been able to see the optical illusion that is described—flat serifs look okay to me? Perhaps my visual acuity isn't good enough.
2) It seems clear that some typefaces are placed on calligraphic models where the original calligrapher finished his/her letters with cupped serifs. That is, they drew their serifs with a curve. In this case, cupped serifs are a stylistic feature...yes?
3) This is not as well documented (or perhaps I have not found the right source), but in letterpress printing, sometimes ink spread around the imprint of the type. Did this ink cause the cupped effect? And if so, did the original type designers and punchcutters want the cupped serifs to be seen in this way? I didn't know if in this case, cupping was used to counteract the ink spread, so that the serifs would look relatively straight.
In this last case, I thought the situation might be a bit like contemporary ink traps.
That is, some designers like how the ink traps look in fonts like Bell Gothic, etc.
And eventually, what was a functional detail becomes a stylistic feature.
At any rate, if anyone has thoughts or helpful references on this, I would be grateful for input and suggestions.