ABSTRACT

Hippolyte Bayard is celebrated for his invention of the direct positive process of 1840. A direct positive process captures an image without a negative. In Bayard’s process, a sensitized sheet of paper is placed into the back of a camera, where the typical negative would have been placed. Direct positives are unique images, however they cannot be easily reproduced. One-hundred-and-eighty years have gone by since Bayard shared his first photographic process, yet, his system remains a mystery. The only extant notes are a series of published letters to the Académie des sciences and to editors in photographic journals. This study explores the scant surviving evidence by re-creating his recipes. Characterization was carried out with densitometry, colorimetry, X-ray fluorescence spectroscopy, X-ray diffraction and scanning electron microscopy.

摘要

希波吕特·贝亚德（Hippolyte Bayard）因其1840年直接正向过程的发明而闻名。直接正向过程捕获的图像没有负向。在贝亚德（Bayard）的过程中，将一张敏化的纸片放到照相机的背面，在该照相机的背面将放置典型的底片。直接正片是独特的图像，但是它们不容易复制。自从Bayard分享了他的第一张摄影作品以来，已经过去了一百八十年，但是，他的摄影系统仍然是个谜。唯一现存的注释是一系列致科学院和摄影杂志编辑的公开信。这项研究通过重新创建他的食谱来探索尚存的证据。用光密度法，比色法，X射线荧光光谱，X射线衍射和扫描电子显微镜进行表征。