Thanks for the report!  I've fixed this in 147 (releasing later today) but I have to say, Canon deserves a good slap on the knuckles for this one!  I had to download and install the ipf8300 driver to see what is going on but apparently when you remove white space from the page, the driver is switching automatically from 300x300 PPI to 600x600 PPI!  There's no way that a simple change of paper length should cause other driver settings to change!  Maybe it's a bug in the 8300 driver or maybe they decided to automatically switch the driver resolution (higher) for smaller size pages, but nevertheless, the driver shouldn't be changing resolution just for sending a change in paper length to the driver.  Nevertheless, 147 will check for that and that should fix it in 147.

Regards,
Mike

That's because back then, your setup didn't call for the driver to switch from 300 to 600 PPI: it stayed at 300 PPI after using the "Remove white space" option.  I noticed that in some situations, the driver will stay at 300 PPI after changing the paper lenth.  For example, if you didn't take off quite as much white space.  Or you had a different paper selected at the time.  It's not consistent when the driver does it's automatic switch-over so the problem won't occur if it stays at 300 PPI when you use the "Remove white space" option.

Regards,
Mike