Digital BW, The Print

> From: cirkutguy [mailto:cirkut@...]
>
> I'm curious as to what information is missing from the color image
> that would be in the black and white. I too find that I often can't
> match the look of black and white film with a color conversion, but
> have always assumed that some amount of messing around would do it.

A B&W image obviously doesn't contain more information than an RGB image,
but the color light coming in the front of the lens certainly contains a lot
more information than what's finally represented on color film in RGB. If
you have a good assortment of filters, you can get spectral responses that
you can't get after the image has been reduced to RGB.

However, there are also dramatic things that can be done on RGB images, such
as subtracting the blue channel in order to make skies even darker, which
you can't possibly do once you've reduced the image to B&W. So in my view,
you get a wider range of effects from shooting color and converting to B&W
in PS, compared to shooting B&W with filters in front of the lens. Also, the
convenience and opportunity for experimentation are self-evidently better
with post-processing. Finally, there's no law that says you can't put
filters over the lens, AND shoot color and convert to B&W afterwards, if
there's some magic spectral response that you can't get without the filter.

--

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco@...