PDF Presentation file size too big

[John Blaustein]

Hi,

I often have to fill out a multi-page downloaded PDF form with multiple text fields.  Some forms open in Acrobat reader and have fields that can be edited and saved.  For other forms, I open the PDF in PS, use the text tool to fill in the blanks, and then use File > Automate > PDF Presentation.  This works fine.  However, the file size of the saved PDF is way bigger than the original form, and I'm struggling to find the correct settings to keep the file reasonably small yet high enough resolution for printing.  

When I first open the downloaded PDF form in PS, there are page settings.  And there are several choices in the Save Adobe PDF dialog.  I'm unsure of which settings will accomplish what I'm looking for.

I'm using the latest version of PS for Windows, and I do not have the paid version of Acrobat.  I can use LibreOffice Draw to edit a PDF and it saves in a reasonable file size, but I'm more familiar with PS and prefer to use it.

Thanks for any help with this.

John

[Conrad_C · Accepted solution]

During the export steps out of PDF Presentation, you should see the Save Adobe PDF dialog box.

The first thing to try is to choose Smallest File Size from the Adobe PDF Preset menu, shown in the picture below.

But zoom in on the resulting PDF and make sure the detail quality is acceptable. If it isn’t, then next time click the Compression tab because that controls the tradeoff between quality and file size in the pixel image that was created when the PDF was opened in Photoshop. Adjust the settings there until you like the balance between quality and file size. If you’re not familiar with the settings, focus on the ones that are highlighted in the picture below. For PDF forms, resolution and detail don’t have to be the highest.

[John Blaustein]

Conrad,

Thank you.  [Smallest File Size] is too low resolution, but I'll play around with the Compression settings.  In my testing with creating a multi-page PDF, LibreOffice Draw (default settings) creates a smaller PDF than PS with the same apparent resolution when viewing the files side by side.  I'm sure the same can be done in PS, so I'll keep testing new settings in the Compression tab.

John

[Conrad_C · Accepted solution]

I haven’t used LibreOffice in a while, but what you said seems to provide more clues. If LibreOffice uses its Draw application to edit PDF files, then that sounds similar to what happens if a PDF is opened in Adobe Illustrator: Because those applications are vector-based, they can maintain the vector-based type and layouts originally present in the PDF file, where a type field might just be defined as a four-coordinate rectangle with some text characters in it; in other words, extremely compact to store.

Compare that to what happens when you open a PDF file in Photoshop: You get a dialog box that asks you, among other things, what dimensions you want in pixels, and what ppi resolution you want. That means Photoshop always rasterizes PDF files that it opens, turning them into pixels. That means it no longer stores PDF objects as vector objects; instead it’s a whole page of pixels at the resolution you asked for. My guess is that should usually make a Photoshop-rasterized PDF a larger file size than if it was opened in a vector application like Draw or Illustrator, or in a PDF viewer/editor such as Acrobat. In addition, a rasterized PDF would make it more difficult to get a good balance between small file size and sharp text and graphics.

So ultimately, if you want to avoid the challenges that happen because Photoshop rasterizes PDF files that it opens, in the future continue to open and edit PDF files in vector-based applications that understand PDF and preserve its compact vector objects (such as LibreOffice Draw, Adobe Illustrator, Adobe InDesign…) or PDF editors (Acrobat, Apple Preview…). 

[John Blaustein]

Thanks again, Conrad.

I'm a photographer and don't really understand vector-based and rasterized.  However, I do understand your explanation of how PS is handling PDF files.  Most importantly, it is now very clear to me that I should be using one of the appliations you mention for my purposes.  Thank you for clarifying this for me.

Yes, LibreOffice Draw is similar to Illustrator.  "LibreOffice Draw is a vector graphics editor that comes as part of the free and open source LibreOffice suite. Libre Office Draw stands as an free and open source alternative to Adobe Illustrator because it offers tools for creating and editing vector illustrations."

[Stephen Marsh · Accepted solution]

This is the challenge of using Photoshop or rasterize presumably live text/vector content.

You can try grayscale mode if colour isn't critical which is 1/3 the file size of RGB.

Even better would be bitmap mode, which would allow higher resolution and better lossless compression, however, I'm not sure if this mode is supported by PDF Presentation to create a multi page PDF.

A native PDF tool would be better for the task.

[John Blaustein]

Stephen, thank you for your suggestions.  I think you are correct that a native PDF tool will work best for my very simple and occasional needs.  I found one called PDFgear that's free and gets very good reviews.  I'll give it a try.