Re: [APML] Push Processing (was Scanning slides)

["Don Westergren" <westergren@netzero.net>]

Alan,

When you get the E200 or Provia400 push processed with long exposures (many
minutes to hours) you will probably see half the push effect.  That means
ask for +2 and the film will be about +1 stop actual.  Ask for +1 and it
will be about +1/2.  What I was trying to convey was that you can not expect
that +1 processing will allow 1 stop less exposure for the same astro
picture.  Both these slide films have significant reciprocity but are still
picking up light with 4 hours exposure.

See also Jerry Lodriguss' response that you don't want black sky.  The trick
is to get your exposure to the point where the sky is not dark black, but
rather some dark gray/blue so you can scan it.  Once the sky fog is reached,
more sky light detracts from the range of light sensitivity (contrast) and
begins to wash-out the picture.  Getting the right exposure of the sky with
slide film is one of the secrets to getting good pictures out of the slide.
Too dark and it won't scan, too light and it's washed out.

Hope this helps,
Don


> I do have one question regarding your comments below. You say that your
> tests indicate that +2 nets a +1 for AP purposes. If I was to ask for a
> push with my film, does that mean I need to ask for a +2 to get a +1?
> Or that it doesn't matter
>
> Thanks,
> Alan



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