Problems opening files "reduced in size" using Acrobat

When you say that "the file produced cannot be opened", what do you mean exactly? Any error messages? What version of Acrobat/Reader are they using? Any other specific symptoms?

When you use the "Reduce File Size" option, which option do you have selected? You might consider using PDF Optimizer instead, as it give you much more control.

George

Hi Neil,

Welcome and hopefully my answer will help.

Acrobat Reduce file size makes use of several compression and image processing approaches to make the PDF file smaller - this may or may not be a very wise thing if you have high resolution images that need to have the image resolution retained (i mention this as I have no idea if the engineering documents have images with detail, or are raster/pixel type pages)

In Acrobat 9, this has been moved under the Document Menu, but in 8 I think it still is under the File menu...

The menue appears next to "Make Compatible with.." - I no longer have 8 installed, so I am not sure what the default is, but i suspect it is (or you are selecting) "Acrobat 7 or later" or "Acrobat 8 or later" - this not only downsamples the images (throws away pixels) but - depending on the object in the PDF - may introduce JPEG2000 or JBIG compression which your customers version of Acrobat - or some other 'PDF veiwing Plug-in, browser or viewer - may not be able to read or parce or display, making this new "Acrobat Reduce file" now incompatible...

Suggestions include;

Try Acrobat 4 or later or 5 - this may not make the file as small as 7 or 8, but it will not use these very modern compression schemes

Try modifying you PDF export presents (under the File menu in InDesign)

Try telling everyone to upgrade (they will then be able to open the PDF files you already made

Try some Buffalo Style Chicken Wings - this will not help much, but they are tastey with a Pint of Stout beer.

Do your part to stop SPDFS

http://michaelejahn.blogspot.com/2008/06/stop-spdfs-stop-transparencide.php

(smile)

Best of luck !

Thanks for such quick responses guys and apologies for taking so long to get back to you.

michaelejahn - As you identify, one of the issues I (like many communicators I think) have is different versions of Acrobat used by our target audiences. A quick survey has indicated that everyone is using 6.0 or above, so I have made the PDF "compatible with" this version as you suggest.

In addition, being selective about which images need to be "maximum quality" and those which only require being "High quality" seems to help.

I have now managed to reduce the average note from 3-4mb to 1mb.

Many thanks again,

Neil

absolutely the right thing - you might even try out medium quality, especially if they are not needing to print, and even consider downsampling to 96 ppi.