Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@y..., mwesley250@e... wrote:

> >  But if you 
> > > are working in a RGB space even with a channel layer set to mono 
> > > would the custom grayscale curve apply?
> > 
> > ----No. Not while in RGB. It will apply at the moment of transition 
> from RGB to 
> > gray. You can set up ways to preview, but that's not the issue here.
> 
> Do you need to preview or will the on screen view be faithfully 
> translated into the new space with profile conversion?
> 
----- You don't really need the preview just for the grayscale - it will be faithfully 
translated as you say. But if you expect to preview color (as in split toned etc), 
that's another story. You need a profile to use under Proof setup>custom. 



> > ---- It isn't so much about the 3 channels or the histogram as much 
> as it is 
> > about the distortion introduced in the workflow when working in 
> grayscale and 
> > have already calibrated to a printed reference by adjusting the 
> gray curve (in 
> > the color prefs).
> 
> Could you clarify the distortion issue for me? Is this distortion 
> caused by the manipulation of the smaller set of data, 8 vs 24 bit?

The "distortion" comes from kinks in the Custom Dot Gain curve. Because it is 
custom (presumably for a given paper, ink,printer combo) it is likely to be less 
smooth than a gamma 1.8, 2.2 or x% dot gain which only uses a midtone 
mark. If you manipulate your gray scale while that CDG curve is loaded you 
are doing all your moves based on that curve. A new paper combo and your 
moves are meaningless (more or less depending on how different your new 
curve is).


> 
> Should you have a whole set of Custom curves, one for each paper? 

---- Yes.


> Could you imbed the specific curve for that image into the file?

----- You can save the file with the profile (=your CDG curve) embedded. You 
can even convert to a different profile for a different paper down the line - but 
then you are begging for tonal breaks in the file - which is kind of the point of 
the workflow I am suggesting here.


> I am wondering how that would work with my RGB pyro scans where I do 
> have a lot of difference on the Blue channel.

------ That's an interesting point that I haven't explored. Whenever you have an 
RGB scan for grayscale there is no reason to assume that every density on the 
film is given the exact same digital value for all three channels. Think about it 
as a three-pass scan. Then add the RGB filters. No one is obliged to use all 
three "passes" the same way. You can set one channel up for better shadow 
separation, one for better highlights etc. Can be a lot of fun!  (and give you a 
more meaningful 3x8=24 bit grayscale). Ah, where is Austin when we need 
him!... <g>

Antonis