Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Steve Kale" 
<stevekale@b...> wrote:
> 
> Hi. I am just working up an image from my new digital camera and 
have come across 
> something that is puzzling me.  The colour image looks great - no 
posterization and no 
> apparent clipping in any channel.  From the RAW file I used 
Capture One Pro with high 
> contrast setting and simply slid the RGB black point slider up to 
the left of the red 
> histogram and then processed (no other adjustments).  In PS, I 
then used the split 
> channels technique to work up a B&W version.  The image is of a 
sand dune against a dark 
> (blue) sky.  My problem is that the red channel appears (on 
screen - I have not printed it 
> yet) to be posterized in the sky.  I want to use the red channel 
because it is giving me the 
> dark sky.  Any ideas as to why this would be?  I can go back to 
the original RAW file if need 
> be. 
> 
> Steve 
> 

Most scanner and digital camera technology today has problems 
rendering certain shades of red correctly, meaning that several 
shades as you see them will turn into a single hue when digitally 
captured, which may not be obvious at first until you start playing 
around with the curves and levels. I have had many problems with 
this myself while scanning or photographing some of my artwork, 
where the reds can turn out to be way off, particularly for a shade 
very close to pure red and a bit towards yellow, which all becomes a 
pure red in the scan or photo.

Hakon
www.hakonsoreide.com
mail@...