Hi, The short answer to the first part of your question question is yes if you set you PSD file to 8x10 inches 300ppi it will be printed at 8x10 inches. The dimensions determine the actual size of the file but we create a high resolution files for print (which is usually 300ppi or more) so that the image prints to a high quality. Our screens can only display 72ppi at a time this is why a print files of 300ppi appears just over 4 times bigger on screen. I hope this helps. Thanks, Sim
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