Hi, forget photoshop resizing, the required final resolution is only 1 pixel wide so any kind of resizing results in rubbish, you have to get the 1:1 result out of Sibelius and then do photoshop copy/pasting and cropping on that. Try A4 in options, margins 50 points, staff size around 25, 4 bars per staff, save as 100%, 90 dots per inch as a starting point.