How much is just a little more than 1/4"? I ask because if as little as 1/16" it wouldn't be noticed in most cases. But in a case where it would be noticed (like how you plan to quilt evenly spaced lines in a fairly small area), I would mark the lines you want to quilt and make sure you quilt on the marked lines rather than using the ruler marks (or put a small registration dot where you want each line to start and stop and line up your ruler accordingly)or I would compensate by not lining up my ruler mark with the previous quilted line but nudge it over a bit to account for the foot being larger than 1/2". If you don't want to mark, use painters tape in a 1" width and stitch right along the edge of the tape.