From: Sandy King (email@example.com)
Date: 04/18/03-07:39:20 AM Z
On reviewing my response to Chris on how the color of the pigment
affects sensitivity and contrast in carbon printing I found an error
in the last sentence, which should read, "the blue would print
fastest and with greater contrast, the brown slowest and with most
contrast, assuming all else equal."
>In carbon printing the color of the pigment has a very big impact on
>both printing speed and contrast. In printing color carbon, for
>example, with yellow, magenta and cyan tissue one finds in practice
>that the yellow prints slower than magenta, and magenta in turn
>prints slower than cyan. Contrast is about the same with yellow and
>magenta, but much greater with cyan.
>I am absolutely certain that if I were to test tissues made with
>pigments in the order you indicated the blue would print fastest and
>with greater contrast, the brown slowest and with most contrast,
>assuming all else equal.
>> What is everyone's opinion about this: "theoretically, the color of
>>the pigment does not affect the sensitivity of the emulsion since the action
>>of the light is on the sensitizer and the gum"....that the only way pigment
>>affects exposure is in its density of holding back light, either by how
>>concentrated it is used in the mix or by the inherent density of the pigment
>>itself (I suppose what we would term "covering power").
>> I guess I am asking this: do you gum or carbon printers always find in
>>practice blue exposes more quickly, and so on down the line in order like
>>this: from shortest to longest times in this order: blue, green, violet,
>>orange, black, red, yellow, brown.
>> Or is that not true?
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