I agree with Ken. As soon as I saw "dark scan" I knew something is
wrong with the scanning. If anything the scan should be normal or light
if the histogram doesn't bump up against both ends. Just like a digital
photo (which it is) using the ETTR methodology you can adjust the final
brightness level downward which is discarding information which is OK.
Going from dark to light however opens gaps in the histogram which leads
to posterization if it's severe enough because you can't create
information to fill the gaps..
Double check what you're doing with the scanner exposure. Starting from
a dark image is definitely not the right way to go.
Chuck Norcutt
On 6/14/2012 10:12 AM, Ken Norton wrote:
> Tina,
>
> I'm not suggesting dropping Silverfast at all. From what I've seen of
> it, it's easier and faster to work with than Vuescan. I've been
> tempted to actually get it myself, but the tightwad in me says "stay
> content with what you have".
>
> Am I correct that you are using a Nikon scanner?
>
> Silverfast, like Vuescan is able to do the two-pass "HDR" like scan.
> This is important as it helps pull the details out of the shadows. If
> the "raw file" is dark and the highlights are more than a stop away
> from clipping, then you really do have a scan exposure problem going
> on.
>
> It really is true--scanning requires an "ETTR" (Expose To The Right)
> methodology to maximize quality. I wonder how much of the "grain" you
> are seeing in the scans is actually scanner noise and lack of bit
> depth coming off the scanner.
>
>
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