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Digital BW, The Print

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Re: [Digital BW] Converting to BW

2002-08-12 by Todd Flashner

> I've got a testy image that I need to convert to a BW for quad
> printing. Lots of trouble with the skin tones. (wedding shot) I read
> through the posts and got some good ideas. The most interesting seems
> to be converting the channels into layers via the Jeff Schewe method.
> How do I do this? Can anyone point me to more info, or describe the
> process. That is, convert the channels into layers? Is this possible
> in 16 bit mode? Thanks in advance.

Since I brought the method up I'll do my best to explain it. It does not
work in 16 bit mode because it requires layers, which 16 bit does not
support.

You can do much of it with keystrokes, but I think I'll explain the long way
so you see exactly what's going on. Others may know how to do it even faster
than me. An action would be a great thing for this!!!

Separate your layers pallet from your channels pallet (drag the tab of one
out of the window).

Start with your background layer selected.  Go to your channels pallet and
click on the channel you want to bring over as a layer (I just start with
Red and work my way down). This should turn off your other channels so your
image displays as your RED channel (okay, a keystroke... You could just hit
CMD+1 to select the red channel only, CMD+2=green, etc). Hit CMD+A to select
all. This is selecting all of the RED channel. You should see the marquee
around the perimeter of your image. Hit CMD+C to copy the entirety of your
RED channel. Now click on the RGB master channel (top one). Now click on the
Background layer in your layers pallet. Hit CMD+V and your RED channel
should now be pasted in as a layer above your background layer @ 100%
opacity.

Now I repeat everything for the GREEN channel. Click background layer, click
green channel, CMD+A, CMD+C, click master channel, click background layer,
CMD+V. Then repeat for the BLUE channel.

You might be able to skip always clicking the master channel and bkgd layer,
I don't remember, but sometimes I found I'd end up pasting one channel into
another channel - this routine helps me keep things straight.

If all went well you will now have the three channels stacked atop of each
other as layers. Click each "layer" on and off to be sure each one is
different from the one below, IOW, that you didn't do any more than once,
and not get another.

Once they are stacked you can change opacities, stacking order, and blend
mode, or even use the underutilized "blend if" sliders (double click the
layers name). You can turn off your background layer at this point, or leave
it on to mess with a desaturated color look, or whatever else you may
stumble upon.

HTH

Todd

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