Rui CarmoI’ve had a number of tussles with PDFs over the years, ranging from tweaking rotation to outright rescue, but sometimes there are more practical issues at hand, such as actually being able to e-mail them to people when they’re… huge.
You can fire up Preview go to File | Export... and pick Reduce File Size out of the Quartz Filter drop-down, but the compression presets Apple defined are so aggressive that the result usually looks like papier maché, so I went looking for a saner way to do things.
It used to be that ColorSync let you predefine settings for this, but Preview in late Mac OS X releases seems to have stopped picking up on those, so I turned to Automator:
Just add the new settings to the Apply Quartz Filter to PDF Documents action – you can start by duplicating the existing Reduce File Size preset and renaming it.
Simply setting the final image resolution to 72dpi works perfectly for the stuff I’m now handling, but you can have a field day with all the possible settings, including sharpening and tweaking colors.