Publisher: Info needed in Document Setup

[Compositor K]

INFO NEEDED IN DOCUMENT SETUP:

File > Document Setup > Document > DPI:
--The document setup panel needs to give some indication of what this setting controls. 

I gather, from a current thread on the subject (_______) that this DPI applies ONLY to raster images in documents being exported to PDF, and then only WITH COMPRESSION. It does not, I am given to believe, apply to type or other vector elements.

But with no clues, a user has to consider all sorts of possibilities. One is that the setting affects type. There is a very similar setting in InDesign (Print > Advanced > Print As Bitmap (with dpi choices 72-600) that apparently DOES degrade type output when Print As Bitmap is checked (which is the default!). 

Perhaps the words "(raster images in compressed PDFs only)" could follow the DPI input field. Then users who are not concerned with raster images, or with compressed PDF export, could concentrate on other challenges, and not have to inquire on the forum.
 

[fde101]

It is also used for any pixel layers you create, and for rasterizing elements using the relevant commands (such as Rasterize & Trim, etc.)

If you set the rulers to use pixels as your design unit, the DPI comes into play for mapping between pixels and inches/centimeters/whatevers.

There are many ways in which that setting is used in the Affinity products, and enumerating them within that dialog box is probably not the most effective use of that space.

A link from there to a help topic would likely be more appropriate if anything.

[Compositor K]

Thanks again, @fde101!

A link to a help topic would probably be a very good idea then, since a lot of people other than myself obviously need to know more about this.

There a recent thread on the subject that seems to have gotten bogged down: