Bottom margin vs. descenders question

[Peter Flynn]

On 05/07/2020 01:54, Reinhard Kotucha wrote:
> On 2020-07-04 at 23:36:07 +0100, Peter Flynn wrote:
> 
>   >
>   > On 25/06/2020 14:00, Peter Flynn wrote:
>   > [...]
>   > > I am not aware of any official typesetting rules for this unless you
>   > >  mean Hart's Rules (OUP) or Turabian (US) or similar. It's been many
>   > >  decades since I looked, but if you can get a copy you could check.
>   > > Or call someone at OUP (I am asking).
>   >
>   > I had one response from a former OUP editor, to say that he would expect
>   > descenders on the bottom line to be completely above the bottom margin
>   > bounds of a page.
> 
> This is silly.  It also means that character protrusion (HZ algorithm)
> is deprecated.

Nonsense. Protrusion is sideways. We are talking about descenders.

> And maybe the left and right margins shall have the same size, the
> preferred fonts are Times New Roman, Arial, and Courier, etc.

We're not talking about left and right at all here. Only about the 
bottom line of a page.

> Ignore these idiots.  

Not if they are paying you to typeset for them. You must perform to 
contract in business.

> If in doubt, simply use your brain.

Now you're talking sense.

> Typography is about optical appearence.  This means that descenders
> should stick into the margin.

Of course they can, that was not the question. The question was whether 
publishers consider this to be taken into measure or out of measure. And 
we're not talking about edge cases or swash characters or decorative 
fonts, just book faces used for the text of conventional book and 
journal work.

On 05/07/2020 04:45, Axel E. Retif wrote:

> Quite right! As I said earlier in this thread, what matters is what
> the eye sees, not what the rulers tell us, and font design gives us a
> clue ---if you put an «x» and an «o» big enough together, you'll see
> that the «o» is really a little bit bigger than the «x», otherwise
> the eye will see the «o» («e», etc.) smaller.
Why are you talking about width? Neither of them descends below the 
beard of the type, and the question was about descenders.

Let me rephrase it: if a face uses descenders which go below the beard 
(and must therefore be set leaded), will a publisher take the measure of 
page depth a) to the baseline, b) to the foot of the beard, or c) to the 
bottom of the lowest descender (if there is one)?

Peter