Technical comments below:
----From iStudio----
At present, iStudio Publisher creates PDF files using Mac OS X's
inbuilt services. It provides no specific options or settings for PDF
processing, although you can add your own PDF processing using Mac OS
X's Quartz filters.
UI issues and implementation issues with the Quartz filters have been documented. ColorSync Users List discussion since PDF/X-3 was introduced. Among other things, no cross-rendering (Perceptual to printing condition, Relative Colorimetric or Absolute Colorimetric from printing condition back to proofing condition for studio display/studio printer).
We are considering adding support for PDF settings
in the future. That's not to say iStudio Publisher creates poor
quality PDFs, and in fact we've made several design choices about the
PDF creation process that results in PDFs suitable for high quality
printing.
OK, to be precise ...
Images are embedded in iStudio Publisher document (.ispx) files in
their original formats. Exporting a PDF also embeds the images in the
PDF file at their original resolution and compression level, so
there's no loss of image quality.
Source resolution is honoured. But what happens to deviceColour, is there control of the assumed source ICC space in assigning or is the assigned source ICC space ALWAYS the Generic xxx Profile set supplied by Apple? For instance, if I know the source is in fact an ISO 12647 space, does Apple's SWOP TROO1 get assigned anyway?
iStudio Publisher can be used as part of a colour-managed workflow.
Document images and other coloured document artifacts (lines, fills,
text, etc) are all tagged with ICC colour profiles, which are stored
in iStudio Publisher document files and are transferred to the PDF.
Per object on a point and pick principle (this object will have fill source ICC space x and stroke ICC source space Y), or on a class-based principle (all objects of this class and that colourant model will have source ICC space x), or what would the above imply? PS and PDF permit per-object colour management with any combination of no colour management, PS colour management, and ICC colour management.
ICC colour profiles can be changed during document editing. Some
printers may require colors to be set to CMYK at document edit time.
For more information about setting CMYK colours, please see the
iStudio Publisher Help page "CMYK colors".
Does this imply that pointing to and clicking on a placed object will display that object's embedded ICC source space(s) and permit manual override per object and per space and per rendering intent? The issue is where the application intelligence for per object colour management stops, because it can be taken all the way in principle. There are interfaces to do that, but there are probably not many users who work with them.
iStudio Publisher creates PDF files with font subsets embedded, which
ensures all font information remains available to remote viewers even
if they don't have all of your document's fonts installed on their
computer. Embedding font subsets involves only including the
individual font glyphs (characters) that are actually used in your
document rather than embedding complete fonts en masse; it helps to
minimize the PDF file size.
Bad idea. Font subsetting appeared in Apple PDD and Adobe PDF in 1993-93 for display and licencing reasons. In PS following Adobe Technical Note 5012 of 1993, updated in 1998, only the font program is embedded whereas any tags that tell of the meaning of the glyphs may be stripped including the CMAP. In the update in 1998, the idea is introduced that the application is responsible for figuring out the meaning of the glyphs and writing a CMAP - which is NOT the same as the actual font CMAP - out as a table and sticking that into the PDF.
PDF 1.6 and higher supports embedding of the intact SNFT indices, no subsetting and stripping away of the glyph run instructions from input to the CMAP through input to the GSUB/GPOS reshaping and on to output of the glyph run as imageable composition. Downside is that OpenType is application-dependent (unintelligent transform, intelligent rendering mechanism) and application-dependent so even registered tag behaviours may not be supported by some specific application whereas the application-independent model of AAT is not supported by Adobe as per its decision of 1997. Application-dependent ICC imaging and application-dependent Unicode imaging is awful - the thrust of FOGRA's argument against application-dependence still stands, but Apple would not licence and it went south from there.
iStudio Publisher controls and sets the
position of each and every character in the PDF rather than relying on
the use of default PDF layout algorithms, so you can also be sure your
page layout will be faithfully reproduced.
The marketing manager for iStudio Publisher needs to get with the program. Characters are non-imageable and do not by definition have the property of being positioned in x-y design space. Glyphs are imageable and are what is positioned.
Henrik