What confuses people is Pixel Dimension vs DPI (or PPI). Viewing size vs Print Size


PPI effects the print size and not the output resolution when you view it on your computer monitor and doesn't effect your image editing or image quality during or after editing..


A picture with pixel dimension of 4115 x 3086 would be too large to fit on the average computer monitor so we resize the pixel dimensions to a more reasonable and easier to view size for the web, e.g. 800 x ? for this web forum. An image that size even my monitor which is a 1920 x 1080 is still way to large and I'll still have to scroll around when viewing it at 100%. But, an image with a resolution of 350 PPI, the actual print size of that picture is 13.226" x 8.817"


When you're editing pictures for the web don't get too concerned about the PPI Resolution, 72 is all that is necessary and is all most computer monitors can see anyways.


When you want to print then you want to adjust the PPI and not the pixel dimensions. However, having said that, When you use software such as Photoshop or DPP you probably still won't have to worry about adjusting the resolution. Most newer Printers do a fine job of managing that on their own so you don't have to worry about. If you use a print shop many of them will request something like 300 ppi or a specific pixel dimension to achieve good quality prints at whatever size you decide on.


Anyways, Maybe this can help better than I can.


http://www.rideau-info.com/photos/mythdpi.html


Or


http://www.photoshopessentials.com/essentials/image-resolution.php