I have a large 300DPI pdf with small labels that are nice and crisp but when imported to Field Maps things get a blurry when zoomed in, verging on unreadable. It defeats the purpose of large area PDFs in there and no one cares if it takes several more seconds to import if that means its full resolution.
The MB size of the PDF and the download to Field Maps are the same, so it seems Field Maps simply imports or renders it at a lower DPI or something?