Re: Pixel Puzzlement

[Larry Cook]

A pixel has no set dimension as has already been stated. The physical 
characteristics of the device being used determines the size of a pixel. 
On a 72dpi monitor a pixel is 1/72nd inch squared. On a 600dpi printer a 
pixel is 1/600th inch squared. And so on and so forth.

Now if you take an image that is 3inch by 4inch on the display and print 
it directly on a printer without any conversion then the resulting 
printed image would be 216pixels x 288pixels which would be 216/600 inch 
x 288/600 inch which is kind of small. If instead the image is printed 
to be 3x4 inches then it will be a 1800x2400pixel image which means 
interpolation of some kind will be used to determine the values of the 
extra pixels needed.

Larry Cook