Ok.. so my 500D has a maximum resolution of 4752 x 3168. If I print 20x30, that means my ppi is only 158. When I google about printing 20x30, there as so many people say they sent 20x30 300dpi. What are they saying? They have a 54MP camera?? So anyway, my question is, is it that bad to tell the software to interpolate it so it is 300 ppi?