I have struggled with getting an exact sized photo printed onto the paper... but I think I figured it out ..... along with a way of getting the best image on your paper. I don't use custom paper sizes of anything fancy - it's just knowing the relationship between the image size (in pixels) and the DPI, dots per inch setting. Anyway, I couldn't really find a clear explanation so I made my own YouTube video. In the video, I also explain the Aspect Ratio and how to deal with the miss-matches. I hope it helps others here.