Quote:
Originally Posted by Telecolor 3007
I know that copying a image from a black and white negative to another black and white negative will produce a positive image. How good is this process?
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Negative material is designed to have low contrast (gamma = 0.5, if you know what that means) and print material is designed to have high contrast to restore the original scene contrast (gamma about 2.0, or often more to compensate for visual loss of apparent contrast). Ansel Adams developed the "Zone" technique to control the negative contrast.
If you copy a negative film onto another negative film, the contrast will be too low unless you modify the development of one or the other to increase it.
On the other hand, reversal transparency film is designed to have high contrast; thus, copying onto another transparency results in too-high contrast unless the original or copy film is specifically designed for duplicating (lower contrast).
The efffect of excess contrast is seen in the early View Master 3D reels, which were originated and copied on Kodachrome. It was quite commercially acceptable to the public, but a knowledgable photographer would recognize the excess contrast.