APPENDIX 1:
THE PLATE-BOX IMAGES: A RECAPITULATION AND SUMMARY OF THE EVIDENCE FOR EACH PLATE.

ALSO, HYPOTHESES CONCERNING
PLATE M.


PLATE: A

DESCRIPTION: A shadowy human figure is partially visible on the plate. The thick, rolled silver-plated copper plate measures about 2 x 2 7/16 inches (5 x 6.2 cm).


Ninth-plate daguerreotype Plate "A"
(Writer's collection.)
 WRITTEN ON BACK: Nothing .

POSSIBLE LENS: Five inches diameter and seven inches focal length. A lens of this aperture and focal length would have maximized light falling upon the daguerreian plate. It would however, have been impossible to achieve any degree of sharpness in the image (in other words there would have been no depth of field) owing to the degree of spherical aberration in a lens with such a ratio of diameter to focal length (f stop would have been only about 1.4).

DRAPER QUOTATIONS: (highlights are mine)
lens five inches in diameter and seven inches focus . . . dark parts of the clothing impressed themselves . . . the forehead and cheeks and chin on which the light fell most favorably, would come out first.[109]
The first daguerreotype portrait consisted of white spots corresponding to the forehead, the cheeks and the chin of the sitter.[110]
By increasing the illumination and prolonging the time I could get the whole countenance. But as you will gather from the size of the lens I used, though it was a combination of a pair of convexes, nothing like a good picture was possible.[111]
HYPOTHESIS: Plate A could theoretically be one of the experimental series of daguerreotypes Dr. John William Draper took on 22 or 23 September 1839 of his assistant William Henry Goode in the chapel of the University of the City of New York. This image would be a partially successful exposure leading up to Draper's first successful "whole countenance".

In this image part of a hand is visible propping up the sitter's head. Dark clothes and hairline, white-spots of the forehead, cheeks, and chin of the sitter are alsovisible, exactly as Draper describes in the above quotations. Facial features are shadowy and confused however, apparently owing to a movement blurred or double exposure of the face. Draper described just such a problem with "double exposures" in his first experiments.[112*]

The lens system described by Draper would not have allowed anything "like a good picture" (in other words there would have been no depth of field, no clearness of focus). This appears to be the exact phenomena visible in this plate-box image.

Once Draper went on to capture "the whole countenance" with this lens, even if out of focus, he possibly accomplished one of the first likenesses of the human face. His closest competition was Alexander S. Wolcott who two weeks later on 7 October succeeded in taking a tiny, three-eighth inch (it measured less than one-quarter inch square) profile daguerreotype of his partner, John Johnson.


CONTINUE
to Plate box images B-D.


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