Photoshop :: Setting Print Size

Here's a quick tip where you can set the magnification of  "View > Print Size" to reflect the actual physical size of your document.
 
1.  Measure the horizontal viewable size of your monitor or laptop screen.  For example: 13.75 inches. 
2.  Note your horizontal resolution. 1366 pixels for instance. 
3.  Divide pixels into inches to get your screen resolution per inch.  1366/13.75 = 99.3 pixels/in  
4   In Photoshop's Preferences > Units & Rulers, enter this value under New Document Preset Resolutions shown in the screenshot.  Save and close.
 
After that,when you select Print Size,the document and even the onscreen rulers will reflect actual size. Now with Open GL graphics cards being fairly common,the odd magnification needed for those results won't appear jagged.