Re: [APML] some comments

["Bobby Middleton" <bobm@koyote.com>]

Any of us who have compared a combined image with a single image at medium
magnification in Photoshop are fully aware of the benefits of stacking two
or more negatives digitally. The final image is simply better. No question
about it.
Whatever you want to call it , it does indeed work Tony
Bobby Middleton

----- Original Message -----
From: <Tonyhallas@aol.com>

> Hi All,
>
>     Some quick comments.... I am fascinated by the light gathering
capabilities of CCD's but can't afford a 2K X 3K instrument right now ... so
that takes care of that.
>
>      Bob Yen has posted an interesting and technical discussion of signal
to noise... I can explain what I doing WITHOUT trying to define it...
>
>      back in the old photolab days we did integration printing to get rid
of the film grain pattern... you would take three identical negatives and
split up the exposures of the print you were making... changing negatives
and thus blending the random grain pattern. This really works, you can see
it in the final print.
>
>     Many years ago Vince Farnsworth found that you could do this digitally
with Picture Window... prior to this, when darkroom effects were attempted
on a single astro negative, the grain got enhanced along with everything
else and... yuk!
>
>       By blending the grain patterns of many negatives, you end up with a
much smoother image... now dark room effects can be applied without the
grain being a problem. Very faint detail now can be seen that otherwise
would be lost in the coarse grain pattern...
> you can debate what to call this, but it really works... I call it an
increase in "signal to noise" for lack of a better description... whatever
it is, it works.
>
>     That's all I can tell you,
>
>          Tony
>
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