In article , Richard Schtzl <Richard.Schaetzl@xxxxxxxxxxxxxxxxxxxx>
writes
>Kennedy wrote:
>
>> It certainly appears to be a lot better, and the contrast range is much
>> greater than the 24bit range of the scanner, since it has 'shadow' and
>> 'highlight' spot metering functions just like the OM-4 to get the best
>> settings for the A to D converters.
>
>They are able to adjust lamp (LED) intensity. But the Coolscans are
>still 3.0 D scaners, 24 or 36bit makes no difference.
>For realy critical slides or negativs there latitude is not big enough,
>resulting in distorted shadows (slide) or highlights (negatives)
>I tested on the CeBIT several scaner (Min****, Nik**, Must**, Ko***,
>Olympus and Polaroid) only the Polaroid was able to render sharp and
>undistorted shadows out of my test slide. It is an expensiv scaner, but
>not much more than the Coolscan 1000, which failed to show an
>informations into the shadows (to dark).
>
The Coolscan adjusts the black level (ADC threshold) as well as the
white level (LED intensity) independently, so you can get all the detail
you want in the shadows. If you really want, all 8 bits in the ADC
range can be set to range only shadows, only highlights, any portion or
all of the slide/negative dynamic range. That's what the spot droppers
are for in the preview mode. You need to run a second preview if you
change the dynamic range too much from the first scan, since it attempts
to approximate the effect by adjusting the data first, and this results
lost dynamic range. The final scan is a full dynamic range scan over
the intensity range you have defined - obviously with the 12bit ADC's in
the Coolscan 1000 this will be better than the 8bit data from the
Coolscan II, which helps for the gamma correction which is applied to
the data output by the ADC.
If your shadows were too dark on a slide it would indicate that the dark
threshold had not been optimised in preview before making the final
scan.
--
Kennedy
Yes, Socrates himself is particularly missed;
A lovely little thinker, but a bugger when he's pissed.
Python Philosophers (replace 'nospam' with 'kennedym' when replying)
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