Digital BW, The Print

> This will give you a very sharp image, with no halo next to the hard
> edges. If you get a halo, you have to back off a bit fromt the 400
> percent. 

I often hear these sharpening halos spoken of as though they are a bad
thing. I thought they were the foundation of unsharp masking. The mind is
fooled into believing an edge is sharper because the contrast around that
edge is accentuated by USM. Yes, the edges may be as small as the grain of
the film, but to USM without creating some degree of haloing, I don't
believe will show much effect at anything less than at or near 100%
magnification, and short of small web images, how often do we view images at
that magnification? Furthermore, if you can see the sharpening effect on
these small web images, if you blow them up beyond 100% you will see some
degree of haloing at the edges.

Clearly there is a limit to how wide you want your halo to be, and how
distinct (the degree of contrast of the halo), but when I hear people speak
of halos as bad, I wonder if the results of their sharpening is even visible
at viewing magnifications.

Comments?

Todd