Digital BW, The Print

Mark Hahn writes:

> Ummm, most film scanners take 3 simulanious scans, one for each 
> channel, to make the RGB file so you do not have the same issues as 
> with interpolated sensor data.  You scan b&w and you get exactly the 
> same dimensions as you do with RGB, plus, with the channel mixing you 
> should be averaging out scanner noise and improving your image.

That doesn't help.  The main problem with RGB conversions has nothing to do
with Bayer filtering or anything like that (although that does produce
an additional problem of resolution, which I have previously mentioned).

The real problem is that you cannot duplicate the unique response of
true B&W capture with any conversion from RGB, because the information
just isn't present in an RGB image.  Just as you cannot produce true
infrared from RGB, you cannot produce true B&W from RGB.

> ... even though they shared your hostile feelings toward
> digital or anything but "real b&w."

I'm not hostile towards RGB conversions, I just understand their serious
limitations.  And I can't really see any reason not to simply shoot
black and white to begin with, if that's what I want.