Why are the French, Italian, and Belgian sized by “panels”?
Foreign posters do not have the same size standards. For example, Australian daybills are printed on paper similar in weight to U.S. 1-Sheets, but their long, narrow size makes them more like U.S. insert posters. Nearly all French posters are folded. (Exception: some one sheet size posters printed in French in the U. S. or Canada specifically for the Quebec market). Standard French movie posters come in three sizes: 15″ x 21″, 23″ x 31″, and 47″ x 63″. And, the German equivalent of a U. S. one sheet is somewhat smaller, measuring 23″ x 31″.