Re: [APML]: Scanner Bit Depth

[Jerry Lodriguss <jml@astropix.com>]

The Astro-Photography Mailing List
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>PhotoCD vs. Scanner:
>
>I think (correct me if I am wrong) that Kodak uses their own RFS 2035 (I am
>not sure if I remember the name correctly) for PhotoCD scans. 


I think they're using a better model than the RSF2035, but I'm not sure of
the number but I think it's the 3075.



>The RFS2035 is
>very highly regarded among the press-photographers here in Vienna.
>Personally I have never used it, but the bigger agency use it, and their
>photographers say it delivers consistently (sp?) sharper images than Nikon
>or Polaroid models. (Jerry, do you agree?) They say, this is because the
>negative and the CCD do not move during a scan. (The scan-movement is
>accomplished by som prisms).


The RSF2035 is excellent for daylight photography.  It is good, but not
great for astro work because you have limited control over the prescan
dialog. You can only set gross brightness and contrast corrections, and
global color corrections. There is no way to manipulate the individual
curves like in the Polaroid, which, IMHO has the best scanner dialog
controls for astro work.

I have tested the RSF2035 compared to the Polaroid and Nikon LS-1000, and
despite the fact that the Polaroid and Nikon technically deliver higher res
scans because they have a higher optical resolution, if you compare the
scans under really high magnification, you will see very little difference
in terms of the resolution. I'd say they are all the same in terms of
"sharpness" if the scans are done in a controlled manner to ensure that all
parameters are equal.

However, the RSF2035 does give much "smoother" scans in terms of the noise
in the sky background. I don't know if this is coming from a better CCD, or
not having the neg or CCD moving during the scan, the type of light source,
a better A/D converter, or better software, or a combination of some of
these things.

If the RSF2035 had the same controls as the Polaroid, I'd be in nirvana.

Jerry
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