On 2007-February-12 , at 19:36 , Michael Grosberg wrote:
jiho <jo.irisson@...125...> writes:
I have a small question regarding that: usually this one-to-one correspondance is for 72ppi (ie. the screen resolution). my screen resolution is indeed detected as 72 by the gimp. why is this different in Inkscape?
Screen resolution is your monitor's width in inches divided by your desktop resolution (the width of course) in pixels. Since people use all sorts of monitors and all sorts of desktop resolutions, the resolution is diferent for each and every user. the screen resolution is traditionally defined as 72 pixels per inch, but this value is not really representative of anything anymore - not even of the statistical average today (it may have been in the past).
Also, note that the operating system can't really tell your resolution: the monitor doesn't tell the system what size it is. In windows XP, normal resolution is defined as 96 DPI, but again, this number is meaningless.
I just measured my own monitor - it's 19" (14.75" width) LCD with a 1280X1024 resolution, and got a resolution of about 87 PPI. So I guess for me at least the number is close enough.
OK, thanks for this detailed and very clear answer. so 72ppi is a kind of legacy in fact? and then 90ppi is just an arbitrary choice which reflects more today's hardware? (arbitrary is ok for me, it's just nice to understand things completely)
JiHO --- http://jo.irisson.free.fr/