I have noticed that the line thickness differences between dorico and a pdf exported version are not the same, at least at the time of printing, since I have tried several browsers, Adobe reader and some pdf viewer software, but always the same thing happens: Either dorico prints the lines thinner (which looks pretty good) or it exports pdf with thicker lines when printing.
I have tried several types of staff line thickness, and again, the same thing happens, the pdf lines are thicker. (When printing)
I am not adjusting the paper size because for some reason, the programs scale it to 97%.
Have you ever notice that? It’s a bit annoying, since I don’t always print from Dorico directly, but sometimes I use the pdf, and it’s uncomfortable that the staff lines are different.