I think 28 patches are far too much on each row. I mean, then each patch is to small to be measured, or the row is to wide to fit inside the eye-one ruler. I think part of your problem is that you have not specified eye-one (-ii1) as option to printtarg when you created the target. Just my guess.
you can define a patch scale factor (and even a spacer scale factor) to increase patch size to make the patches larger when using printtarg patch/spacer scale -a ; spacer scale -A. like this you will get less patches per row too. refer to the document printtarg.html in the doc folder of argyll regards joe
