When exporting from PowerPoint to PDF, how do I prevent image compression?

Solution 1:

If you're using Powerpoint 2007 or 2010 then the max DPI it will save a PDF at is 220, even if image compression is turned off.

You could install PDF printer software like PDFCreator then "print" your presentation, make sure to check the High Quality checkbox. In PDFCreator click Options then Formats -> Compression and change the compression from Automatic to the level of compression you want e.g. JPEG-Minimum. I wouldn't recommend completely turning off compression as this will create a huge PDF document.

http://sourceforge.net/projects/pdfcreator/

Solution 2:

Note that the export bitmap resolution may be increased to a maximum of 300DPI by making the following registry change for the corresponding version of PowerPoint:

2016 : HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\PowerPoint\Options
2013 : HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\PowerPoint\Options
2010 : HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\PowerPoint\Options
2007 : HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\PowerPoint\Options
2003 : HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\PowerPoint\Options

Add a new DWORD value, ExportBitmapResolution and set it to decimal 300.

Full info from Microsoft at : http://support.microsoft.com/kb/827745/en-gb

Solution 3:

Best solution, as of August 2016:

http://www.zamzar.com/convert/ppt-to-pdf/ - I have spent about half a day testing different online and offline methods. At the end the one that I found to convert a presentation to PDF with a perfect quality is Zamzar.

Things that I have tried and the image quality is still terrible

Creating a Google Presentation and export as PDF: Fail
Converting a Power Point presentation to PDF: Fail
Trying the registry trick as suggested by Micro$oft: Fail (I don't why, no difference still).

Solution 4:

I found a way, 2 easy steps

Save the Powerpoint as PNG first, it would be in several files if you have more than one slide
Just search for "convert png to pdf" in Google and use an online tool to convert PNG to PDF

That should work