Hi Jim,
Please correct me if my maths is wrong...
Assuming you are using Sony A6000 with your ED80, that gives less than 1.4 arcseconds per pixel.
Given that your EQ5 mount has a periodic error of 30 arcseconds, which to my knowledge would be awesome for EQ5, that would result is 30/1.4= about 20 pixels, meaning a small star that should normally be represented by one pixel would be stretched over 20 pixels, given perfect polar alignment and an exposure equal to a full worm cycle. Even with shortish 60-second exposures I would dare to say you would be throwing away most of your subs, even with perfect polar alignment. I am afraid it would also be the case with AZ-EQ6; it needs guiding at that resolution, unless you are prepared to accept elongated stars.
Echoing others, the cheapest solution would be to guide with EQ5
