----- Original Message ----- From: <editor@xxxxxxxxxxxxxx> To: "List for Photo/Imaging Educators - Professionals - Students" <photoforum@xxxxxxxxxxxxxxxxxx> Sent: Tuesday, May 13, 2008 7:42 AM Subject: Re: Pop Photo Resolution Lines Per ? : But all MTF tests are done using line PAIRS per millimeter. Thus you would convert your x lines per mm into x/2 lp/mm (for comparison purposes) : : Further, your math is wrong. 2100/25.4 = 82 lines, which translates into 41 lp/mm. Keep in mind that these tests are at full contrast (i.e. Black lines on white background) so comparison to normal 50% MTF is difficult. : : Michael : Sent from my Verizon Wireless BlackBerry on top of that digital resolution along the x/y axis differs from that on an angle.. so resolution drops further, unlike film resolving power an example (and this is about as 'actual' an example as there could be!) resolution= pretty good []=pixel [] [] [] [] [] [] [] [][][][][][][][][][] resolution, not so good (jaggies) [] [] [] [] [] [] [] [] karl