If I want to click some photos from a Mobile Phone Camera or a DSLR camera in such a way that when I view them on my 12.9" iPad Pro it should occupy full screen when clicked Horizontally and also if I click it in Portrait Mode. If I want to have this. What size ratio should I take the photos ? So that it occupies full screen on the 12.9" iPad Pro ? My. Amera this ratios available 1:1, 3:4, 9:16 and Full Screen Mode. Which Ratio should I click the Photos ?