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A golden rule in graphic design is to always start with the source design files and re-export once the appropriate changes have been made.

Often in digital printing in publishing this is not an option. What exactly are the repercussions of opening a PDF with Photoshop, making alterations, and saving in PDF format? What kind of quality is lost?

I realize that the actual components that form a PDF are complex and hard to understand, but does this hurt the integrity of the PDF components?

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    You would be much better of editing in illustrator. Still no guarantee the pdf is going to cooperate. – joojaa Apr 21 '15 at 17:13
  • Any reason why illustrator plays nicer with pdf? – maxwell Apr 21 '15 at 17:29
  • Added a bit of an explanation as an answer, that covers the subject a bit more. Tough its still quite brief. – joojaa Apr 21 '15 at 17:59
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The nature of the PDF can carry a lot of weight. There's no real solid guide to what exact repercussions may be without knowing the original application which generated the PDF and the setting (job options) used when creating the PDF itself.


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Repercussions of opening a PDF which was not created by Photoshop in Photoshop:

  • All art is rasterized. You lose sharp, crisp, vector art and gain pixel art with anti-aliasing.
  • All Text is rasterized - no more text hinting, no vector text outlines, everything becomes a pixel. There will be no "live" text, so you can't simply alter text with the type tool. You have to treat text as art, because that's what it will be.
  • No layers -- all art is one layer. This may or may not make editing difficult.

Essentially if you open a non-Photoshop PDF with Photoshop you convert the PDF to one big image. This may mean the overall file size will increase, sometimes dramatically. And it almost always means editing is much more difficult.

It's generally a bad idea to rasterize an entire PDF by using Photoshop. There are better applications out there to edit a PDF, the obvious being Adobe Acrobat. Photoshop is not designed to edit PDF files.

However, if you are seeking a JPG or PNG of the PDF, then using Photoshop is fine and shouldn't be an issue at all for that particular need.


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If the PDF is a Photoshop generated PDF with "Maintain Editing Capabilities" set to on:

  • Any loss would depend upon version and feature sets. If you save the PDF from Photoshop CC and open the PDF with an older version of Photoshop, some areas may be flattened or expanded to maintain appearance. This is similar to opening a new version .psd with an older version of Photoshop. It all depends upon what features were used in creating the file.
  • Fonts. If the original file uses fonts not installed, you may run into some font replacement issues.

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If the PDF is a Photoshop generated PDF without "Maintain Editing Capabilities" set to on:

  • See Item #1 above

Some applications save multiple file versions within the PDF wrapper, and that's all PDF is - a wrapper. For example if you save a PDF using Adobe Illustrator with "Maintain Editing Capabilities" set to on, you actually save both a .pdf and a .ai file all within one PDF file. If you open that PDF later with Illustrator, the .ai portion of the file is read, not the pdf portion. The same holds true for Photoshop -- if you save a PDF from Photoshop with ""Maintain Editing Capabilities" set to on you save both a .pdf version and a .psd version all within a single PDF file (wrapper). Opening that PDF later with Photoshop reads the .psd portion of the data.


Also realize the version of the PDF will play a large role in how inherently editable any PDF may be. Saving to PDF1.3 (Acrobat 4) will flatten all artwork and you'll lose all transparency and layers. Saving to PDF 1.4 (Acrobat 5) will maintain transparency but not layers. Saving to PDF 1.5 or better (Acrobat 6+) will maintain both transparency and layers.


In the end..... it all depends upon the PDF and what application generated the PDF.

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As indicated, it is always preferable to open the pdf in illustrator due it will keep the vectorial data of the pdf (of course, if there is in it). If you open the pdf in photoshop the file will be rasterized into an image, losing all the data. I think you'll have more chances for modifications within illustrator.

Anyway, editing an exported pdf will be always tricky and you'll have probably issues.

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Illustrators page model is much closer to PDF. In fact PDF started out as a replacement/successor for Postscript and illustrator was and still is a postscript engine of sorts (it is now a PDF engine).

This is a bit over optimistic tough. While illustrator can read a PDF file fine and can interpret most PDF features graphics wise to vector. There is a few huge problems:

  • It needs to turn those objects into illustrator primitives. While illustrator has many of the exact same primitives as postscript. few of them are missing. Edit: To clarify this means while looks may be preserved all features may not be.
  • It will only use fonts that you have installed on your system. This is not so much a technical limitation but rather a licensing ideology Adobe adheres to.
  • Illustrator does not understand interactive items.

In general the document was usually somewhat compromised when exported to PDF. There's for example no way to rebuild the text boxes that were in the document, and quite often the text threads in PDF files are broken beyond repair already at the source export. So as a general rule PDF flattens the data in a way that makes PDF a one way conversion. While some of these can be handles many of them can not.

For simple things, that do not rely on flowing text such as logos etc. There's a high likelihood that Illustrator retains most if not all data. But as complexity raises so does the likelihood of breaking something.

  • As said, Illustrator can read and write PDF. However, a lot is lost in this process (structure (needed for accessibility), annotations (which includes form fields), logic and so on…). So, Illustrator is NOT a general purpose PDF editing tool. If you know what you are doing (haha), Illustrator can be very useful, mainly in print workflows, where all the PDF has to do, is going to an output machine. Because PDF is such a powerful format, there are only very few PDF editors around. – Max Wyss Apr 21 '15 at 19:11
  • Because embedded fonts are normally subsetted, it is not possible to use them for editing, because the characters you need may not be available. Therefore, you must have the font on your machine, in order to edit text. This has not much to do with honoring the licensing by the font makers; it has simply technical reasons. – Max Wyss Apr 21 '15 at 19:14
  • @MaxWyss well illustrator wont open the font even if you include the entire font. Theres no reason it couldnt create a temporary font. I do this semi regularly myself. Theres really no good way to completely edit pdf files not because you couldnt be feature complete but mainly becuase the program exporting may have messed the stuff allready. But yes there are better apps sure. I was jut adding this answer because i was explicitly asked to explain why illustrator is better than photoshop. – joojaa Apr 21 '15 at 19:39
  • @MaxWyss anyway added clarification about your point. Anyway your right pdf is a insanely complex format. And quite frankly there are times when the ONLY way to edit them is to open the PDF in a text editor and mannually write the changes the sections/ append changes (after decompression). Yes i do write PDF by hand every 3 months or so. – joojaa Apr 21 '15 at 19:42
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    @maxwell im not certain how much info you can take in. Lets just say editing a pdf file is not trivial as it has lots of obscure features that ALL may be lost. I might do a bit of writing tomorrow when i have a keyboard. – joojaa Apr 21 '15 at 19:56
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This is an overly simplistic view of PDF and its capabilities. PDF is NOT an image file; it is possible that its sole contents is images, but that would be a special case.

That said, Photoshop not a PDF editor; it can be used as a helper for raster images.

When it comes to last second modifications, the products by Enfocus or Callas Software are the tools of choice.

Also note that the editing capabilities of Acrobat DC have been improved over earlier versions.

  • "This is an overly simplistic view of PDF and its capabilities" No that's exactly what I'm saying though! I realize that a PDF is very complex with all sorts of objects in it. That is why I am inquiring about the nature of repercussions.. – maxwell Apr 21 '15 at 17:27
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    The question is absolutely legitimate, and for certain uses, Photoshop would actually be the tool of choice (such as noodling around with separations). The same limitations as mentioned with Illustrator (losing a lot of the features of the document) apply for Photoshop too. In short, Photoshop is one tool to work with PDFs, among others, and you really have to know what you are doing… – Max Wyss Apr 21 '15 at 19:16
  • You could go a long way further if you would explain a bit more. So if you would roll your comments in the answer it would be better. +1 for the total effort tough. – joojaa Apr 21 '15 at 20:05

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