Re: dpi of scans/jpg's: 300 or 72?

Regarding this discussion:
You will get a better result when you scan at 300, then reduce dpi to 72.
When you scan at 300, and reduce the dpi, the resulting image is dithered.
(at least it is with jpg's.)

If it simply removed every other pixel or so, the result would be terrible.
Instead, a mathematical formula preserves some of the info from the 
original sized scan thru the process of dithering.

In dithering, the color values of adjacent pixels and removed pixels are
averaged to make smoother transitions. Thus, even when a pixel is removed
by reducing the dpi of an image, some effect of its presence is still
evident, in the color values of the remaining pixels, which will have been
adjusted, or smoothed, by dithering (like interpolation in math,
or also similar to the effect of anti-aliasing.)

Thus, at least for jpg's (any photo), scan at 300 then reduce dpi to
72 for the best web results.

Hope this helps explain why,
jimmy

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