Digital BW, The Print

>...I want to print through photoshop, as ut3d are meant to
> do (if I'm not wrong),

Well, it was hoped that a color profiling system would be able to
control the inkset and allow control more in line with a color workflow.
Unfortunately, the results with that workflow were a little less useful
than I'd hoped for.

As a practical matter, curves, either in Photoshop or a rip like QTR,
are the best way to control the inkset.

>  I want to split tone my images as shown
> here : http://www.paulroark.com/BW-Info/Split_tone.pdf
<http://www.paulroark.com/BW-Info/Split_tone.pdf>
> I need to work in rgb and print it as an rgb image,

The curves are clearly RGB curves that need to be applied to an RGB
file.  However, it's a gray scale file that is converted to RGB, and the
colors are false colors in the workflow I use.

> and here are my doubts :

> I'm not able to achieve the split toning without altering
> totally the luminosity of the image (when I print) (it gets deeply
> darker), ...

The very simply curves I used in the example above will only work if
mild.  If they are pushed too far they will affect the ramp.

For most split tones I've done I use a carbon curve for the warm.  This
is the easiest curve to make because it's just one channel.  Then I
usually have a neutral or cool curve for the other end.  Both of these
curves are, ideally, made carefully enough that they result in a linear
output.  Then I use selections to determine which goes where and how
much.

Note that most of the split tones people talk about here are single
curves that simply have warm highlights and cool shadows, or the like.  
A split that is between selection areas can't be done by QTR.  Photoshop
curves and IJC are the two workflows I've used for these types of split
tone printing.

Hope this helps.

Paul

www.PaulRoark.com <http://www.PaulRoark.com>



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