Digital BW, The Print

Hello Lincoln,

the approach I take does take this into account.

I first set up a curves adjustment layer, then a channel mixing 
adjustment layer (and a final curve adjustment layer just for good 
measure).  You will quickly come up with your own starting values in 
the channel mixer layer (ie. then put it into an action).  Now you go 
into your first curve adjust and tweak your individual channel cuves 
to adjust for sky and stuff.  I generally rely more on dropper 
information than histograms, but either will get you there.  For me 
this approach is totally intuitive and logical since I understand how 
the color channels are affected by the curve adjustments and channel 
mixer.  Your sky example is exactly why you want to control your 
curves locally since, in general, you don't mix very much blue 
channel into your b&w image and you often start out with dark and 
noisy skies (from digital cameras).  If you just bump up your blue 
curve in the sky region you fix this without negatively impacting 
your image elsewhere.

I agree that you want to pick one approach and fully understand how 
it works and what you are doing when you play with curves or sliders.

mark

> > Hello all,
> >
> > It is interesting to try all these methods to convert color scans
> > into b&w (split channel, etc) However, there doesn't seem to be
> > an effort to tie in the information that is available in the
> > histograms.  Does anyone look at individual channels and say, "
> > well that hump in the 200zone of the blue  channel is the sky" ? 
> > Or that  hump in the 100zone of the green channel is the lawn" ?
> > and that  50 zone hump of the red channel is the trunk of the
> > trees", and so on...?"
> >
> > I ask these questions because converting to b&w doesn't seem
> > to have any logical approach.  I find myself moving the sliders
> > around without really understanding how I arrived at the image
> > that I finally choose.
> >
> > Does anyone have a method for this "madness"?
> >
> >                                   Lincoln