Use images that you are allowed to reproduce. You are responsible for checking the preview, paper choice and printed dimensions before using the result. The tools prepare a PDF but do not control printer hardware, colour accuracy or driver settings. Test on ordinary paper before an important print.
Before you print
Use Actual size or 100% in the PDF print dialog. Match the paper format and disable any further resizing in the printer driver. The preview shows the PDF layout, not a guarantee of your printer’s printable area. Start with ordinary paper and measure before using photo paper.
Job limits
Jobs are limited to 40 photos, 30 MB and 50 megapixels per image, 50 copies per photo and 80 PDF pages. Poster dimensions can reach 2000 mm per side, but page count and device memory may limit a job earlier. The automatic arrangement is practical rather than guaranteed to use the fewest possible sheets.