But most photographs aren\'t just well-defined black and white boundaries - in fact, none of them are. So when faced with angles, gradients, or irregular shapes, the computer has to use its stored rules to guess what color the new pixels should be. In theory, the superior routines allow the personal to do a pretty good job at smoothing out the image when the resolution is increased and all those new pixels are put in place. In practice, unlike in the movies or on TV, you cannot get information out of a picture that is not there. That little black dot on the horizon is not going to turn into an umbrella when you double the resolution, it will just be a larger black dot. So if you need a \"bigger picture\" than you\'ve, why not use interpolation? The trick is that the interpolation done in your camera is not the same as the interpolation done in your computer\'s editing software.\r\n\r\n

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