Digital BW, The Print

Editor P.O.V. Image Service writes:

> Wide in the sense that it is "spectrally wide," yes.  But shooting B&W
> digitally is much like converting a color slide to B&W...

Identical, from an information-processing standpoint. That is, both have
the same serious drawbacks.

A pure B&W digital camera would produce very nice B&W indeed, since CCDs
are naturally good at monochrome capture, and the absence of color
filters would eliminate the resolution loss and some of the aliasing
that occurs in color digital cameras.  Unfortunately, there seems to be
no demand for a pure B&W digital camera, so none exists.  And since
there's no such thing as interchangeable image sensors (and probably
never will be, since that would partially kill the golden goose that
digicams represent for manufacturers), there may never be a true black
and white digital camera.

> The exposure latitude, or number of exposure zones, representable is
> VERY narrow, when compared to B&W film..

Under ideal conditions, CCDs can record 17-18 stops.  That requires
large photosites and a carefully designed chip with carefully designed
support electronics, though, and the CCD must also be actively cooled to
preserve shadow detail.  It's not really practical in ordinary digicams,
and so the average digicam actually turns out to have less range than
B&W film.  It's hard to beat the simplicity of a piece of plastic with a
light-sensitive coating.