Re: crop marks in PDF for printing

[Alexander Kobel]

On 2016-11-04 11:56, Henning Hraban Ramm wrote:
> Even if your PDF pages are bigger than the intended printed pages, you could easily define 
> "trim box" and "bleed box" of the PDF. A printshop that cannot handle these 
> nowadays is no serious business. But then they could do that for you, too.
>
> (BTW I studied typesetter and printing engineer, worked in printshops for 
> decades.)

That reminds me to ask a professional a question that I was pondering 
about several times earlier on.

In many brochure-bound volumes of more than two or three sheets (say, 
60+ pages), the paper is cut to align flush when the brochure is closed. 
 So the inner sheets are (sometimes significantly, say in the order of 
5mm per page or 10mm per sheet) narrower than the outer ones.  Does / 
should this impact the layout of the page?  And if so, how?

In particular, should the line lengths be varied throughout the book 
such that the margins remain identical, or should the inner margin be 
changed, or the outer one?  IIUC, traditional (text) layout rules are 
meant to compensate for the visually smaller inner margins when the book 
is opened, so they say to /increase/ inner margins. On the other hand, 
many classical layout rules are based on the fact that the outer margin 
should be as wide as twice the inner margin (hence, whitespace appear 
identical).  But if the inner sheets are smaller, but the binding offset 
/increases/ inner margins, the outer margins get even more compressed?

For music, we have more freedom in layout; the needs are totally 
different from the ones for text, and things like character count per 
line do not apply.  As far as I'm concerned, the most important 
consideration for sheet music page layout is proper places for page 
turns, and as little of them as possible - without sacrificing 
readability.  Margins or their symmetry seem to be much less important 
than for text.
Still, for aesthetical reasons, I could imagine that either ratio 
between margins and line length, or the absolute margin widths, should 
be the same throughout the book.  Opinions and/or professional 
authority-based knowledge, anyone?


Cheers,
Alexander