Bleed Setings

[MikeW]

5 minutes ago, thomaso said:

Isn't it simply a shorter term for "rectangle around all content". I assume it doesn't have to serve any purpose besides communication about it.

Hm? I'd say if you draw or scale an object – in any layout app – up to paper size than it results in an ArtBox in page's size.

No, it's not simply a box around all content. In all/most applications, the artbox is equal in size as the cropbox. If there is no bleed, then the artbox is equal to the page size (as are the trim, media, etc., boxes).

So here is a PDF I have changed the artbox size. The page size is US Letter. The only "art" is the rectangle. Here you can see (screen shot from Acrobat) I have changed the artbox (the red rectangle in the screen shot is the artbox) to just a bit larger than the only page content, the black rectangle.

The only application I have installed at the moment that can use the artbox is ID.

Many applications ignore pdf boxes and just release all the clipping masks involved and place the content itself and the net effect is the same as what ID is showing. Except when opening a PDF, then usually the trim box is used, which without bleed is the paper size.

ID has additional options that even without an artbox sized to the art itself, can import at a bounding box size (which typically equal an unset artbox). This is useful as it effectively crops a PDF to the page contents, something that QXP lacks and saves few seconds of time.

Mike

[thomaso]

Ah, I see now. Yes, indeed, the artbox isn't simply a box around all content but more often simply the pages crop box by default. And it could, for instance, even be used as focus area on a page with more objects around it:

"The art box (PDF 1.3) defines the extent of the page’s meaningful content (including potential white space) as intended by the page’s creator. The default value is the page’s crop box."
https://wiki.scribus.net/canvas/PDF_Boxes_:_mediabox,_cropbox,_bleedbox,_trimbox,_artbox

Adobe itself apparently did not expect intense use of the artbox when they defined for PDF/X-4 standard:

"PDF/X-4 files need, next to the MediaBox, a TrimBox or an ArtBox, but not both."
https://www.prepressure.com/pdf/basics/page-boxes

Now I wonder why you mentioned this speciality of the artbox – do you miss its use in Affinity?

[MikeW]

10 minutes ago, thomaso said:

...

Now I wonder why you mentioned this speciality of the artbox – do you miss its use in Affinity?

Nope. I don't miss it at all. My only point was that old graphics like what was used for demonstrating pdf boxes can be misleading.