Page:TheAmericanCarbonManual.djvu/41

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SWAN'S CARBON PROCESS.
31

be secured with a thin negative; and that by using a thicker film of insoluble matter, less intense in color, the excessive contrasts of a hard negative may be softened, thus materially ameliorating the faults of bad negatives in either direction.[1]

With a good negative, neither weak on the one hand, nor too intense on the other, there is no difficulty in producing perfect results, rendering between pure white and deep black every minute gradation, from the most delicate demi-tint in the lights to the least illuminated detail in the shadows.

The tissue is prepared, therefore, in each tint to suit negatives of three qualities. These are numbered, Nos. 1, 2, and 3. No. 1 possesses the smallest proportion of color, and is suited to the production of harmonious prints from negatives in which, from the nature of the subject, from under-exposure or over-intensifying, the contrasts are abrupt. No. 2 is suited to good negatives of normal character, in which the densest parts are not absolutely opaque. No. 3 possesses a large proportion of color, and is suited to thin, soft negatives, a little lacking in force and intensity. By a classification of the negatives, and the use of a suitable quality of tissue

  1. We say, that by the employment of a kind of tissue possessing a suitable proportion of pigments, the faults of weakness or of hardness in the negative may be ameliorated. We must not be understood to say altogether corrected; for after all that can be done in the way of compensation, defective negatives will produce defective carbon prints. And here it may be well to mention that the kind of negative which suits best for Mr. Swan's process is a negative of full average density, with full detail in the shades, such as is got by ample exposure and development. There should be some, although little, absolutely bare glass; but whatever deposit of silver there is on the deepest shades should be a pure photographic deposit, and not “fog.”