I recently attended the George Eastman House's daguerreotype workshop. If I
remember correctly, it was asserted at the workshop that one of the reasons
that daguerreotypes have such astounding resolution is that the layer of
light sensitive silver is only one or two molecules thick. It was suggested
that other processes, relying on perhaps *hundreds* of layers of light
sensitive molecules, would therefore have a "dispersion factor" to deal
with, and would therefore be that much less "sharp" as a result.
This made good sense to me, but a friend recently asked me this: If that is
true, why did Southworth and Hawes reportedly "double plate" all their dag
plates with an extra layer of silver? Wouldn't that effect the relative
resolution of their dags, vis a vis their peers?
Further, how would this double plating of the dags effect the sensitization
process which took place over crystals of iodine and then bromine? How
would the sensitized layer over a double layer of silver render a benefit
over the single layer if it's only the top few layers of molecules which are
being sensitized anyway?
Thanks in advance.
Jon Bailey