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RE: [APML] Pushing & Mars
Gary,
Push
processing expands the contrast range of the film and increases it's
speed. Astrophotographers typically push process film because many of the
objects we photograph are low in contrast in addition to being dim.
Technically if you push the development of the film, you should adjust the speed
setting on your light meter. A one stop push does not necessarily equal a
one stop adjustment on your meter. It is typically less. I believe
E200 requires a 1/2 to 2/3 stop increase on the light meter. But in
astrophotography this is usually not necessary because we expose to the sky fog
limit. I have no experience with planetary objects, but since they are
much brighter, you may want to adjust your speed rating . Just remember 1
stop push does not equal one stop increase in film speed. Read the
instructions with the film or go to the Kodak web site and you will find the
information you need on the correct speed rating.
Kirk
Carbo
I have 2 newbie questions for the group.
1. When pushing slide film are you supposed to change the ISO
setting on the camera to reflect your push, or leave the setting at the
correct film ISO and let the developer do the push?
2.
What would be a good film speed to use for pics of Mars? Fast (800) with
short exposure or slow (200) and a longer exposure?
I'd appreciate any
guidance anyone can give me.
Gary Hatfield
Thaxton, VA
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