When exporting a pptx to pdf the font size of charts is not consistent. The font size is different when I generate the pdf from a windows service as oposed to generating it from a windows form application. I had to set SaveMetafilesAsPng to false to get the charts to look good in the pdf.
My guess is that the pdf conversion process converts the charts into wmf pictures which might be the reason why the font size may differ from the pptx. Obviouly I could work around these issues but it is quite anoying if the font size changes as soon as I deploy it to the server as a windows service. Some insite would be appreciated.
IPresentation presentation = GeneratePptx();
IPdfOptions saveOptions = new PdfOptions();
saveOptions.SaveMetafilesAsPng = false;
presentation.Save(@"c:\test.pdf", SaveFormat.Pdf, saveOptions);