Tinted glass plate negatives

Deborah Tint <dtint [at] verizon__net> writes

>I am scanning a set of 8x10 dry plate glass negatives dating from
>1910-1937.  We are scanning them to create positive digital
>"prints". In some cases the whole plate or selected areas have been
>painted on the emulsion side with a transparent deep magenta
>material.  ...

This type of the negative retouch was used when the too contrasty
negative need some treatment to get details in the shadow parts of
the picture. In that time especially around the 1910s the change of
positive technology would be a special reason to use this method.
The negative process was created originally for printing out paper
which needed a higher contrast and density, but later, when the
developing out papers was used widely, that material was not able to
make good quality print from these negatives. The DOP materials
needed lower contrast and because the missing "automasking"
possibility of the POP papers, the DOP papers could not to show
enough details in the shadow and highlight parts.

The magenta color for the blue sensitive papers worked as a higher
density like as seems like with naked eye, so the original effect
working only on a blue sensitive material. To imitate the similar
result probably the blue part of the color scanned picture
(transform to B&W) can be the closest to the original looking. Or a
blue filter foil over the glass plate (while scanning) can be a
successful method.

Balint Flesch
Archaltfotokonzerv


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                  Conservation DistList Instance 25:46
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