Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Garry Sarre" 
<garry@s...> wrote:
> 1/ is upsizing in PS Bicubic 16bit superior to upsizing in 8bit.
Theoreticaly yes, and this may be one of the few situations where 
you will probably see the results. What is even better, however, is 
to get your hands on an app that uses a more sophisticated 
interpolation algorithm like Spline-32 /64/128. Lanzcos, or Vector. 
If you're on Win platform, probably the least expensive is either 
the combo of Panotools (free) and PT Gui ($40.00) or Qimage, (40.00)
in 'save to file' mode if you don't want to print it right away. 
Qimage is also excellent at downsizing on the fly, and feeding the 
Epson driver only what it needs so no downsampling gets done by the 
driver. Genuine Fractals got a lot of attention for a while, but IMO 
it is way over-rated, slow, and forces you to keep it around to open 
and upsample those proprietary .stng files it makes.


> 2/ Apart from levels and curves tonal adjustments, what else 
> degrades image quality in 8bit more than 16bit.

I've read that sharpening is best done in 16-bit, at least in theory-
 can you see the difference? unlikely, but it can't hurt. 
> 3/ When Printing B&W from an RGB image does changing from 16bit 
RGB 
> to 16bit greyscale (editing on smaller file size)and then back to 
> RGB for printing degrade the image more than simply staying in RGB 
> all the way?

I don't think so, though I'd be curious in other's opinions myself. 
If you're not adding color info, you're simply triplicating the BW 
info when you convert back to RGB, I see no reason any degradation 
should occur. I have noticed that with cheap low-bit flat-bed 
scanners you get a smoother image scanning in RGB and converting to 
BW in PS, but that's not quite the same.

Steve K

> 
> Any help appreciated
> 
> Garry Sarre
> 
> www.sarre.com.au