Digital BW, The Print

Thanks Paul.
One thing I was not clear about is that I only cut back to 8 bits
AFTER working on the image in PS and finalizing it. Putting that
aside, what you say makes good sense to me.
I'll store at 16.
Ginny

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Paul D. DeRocco"
<pderocco@...> wrote:
>
> > From: ginnylady33
> >
> >   I've been scanning via my 9000 at 16 bits but ultimately burning
> > files onto Gold CDs for storage at 8 bit. It saves much space. I'm
> > wondering if this is an error in judgment.
> >  I know from experience that, at times, something that you'd expect to
> > be a 'better methodology' may not be. For example, I've done detailed
> > testing with my 9000 scanning B&W negs at 1x/16 bit vs 16x/16 bit
> > superfine mode. (Which takes forever to scan)
> 
> You should never store a raw unedited image from any source in 8-bit
mode.
> Once you've carefully compensated for the exposure, and worked on the
> picture until you're sure you've brought out all the important
detail, and
> are ready to print, then and only then can you safely cut back to 8-bit.
> 
> Be aware, though, that the degradation that occurs with the lower
bit depth
> won't appear in all images, and may only cause a problem occasionally.
> Rather than try to judge each image, it's simpler just to keep
everything in
> 16-bit for archiving purposes.
> 
> Another thing that may be confusing things for you is that noise in the
> image actually compensates to some extent for the shallower bit
depth. If
> you create an artificial noiseless image (or even use a noise filter
on a
> real image) you can create a situation in which, after editing, you see
> posterization in an image. However, the presence of significant
noise in an
> image prevents this from happening. In effect, the noise allows the
> representation of finer gradations than the simple number of bits would
> suggest, through the mathematical process known as dithering. (This
is how
> inkjet printers work, where smooth gradations are represented with
only one
> bit of resolution: on or off.)
> 
> In other words, you may be able to mask the problem by using 1x
scanning,
> since that produces more noise. If you do 16x multi-scanning, to
average out
> some of the noise, you'll generally get better images, but you'll be
more
> susceptible to posterization if you cut back to 8 bits.
> 
> --
> 
> Ciao,               Paul D. DeRocco
> Paul                mailto:pderocco@...
>