ABSTRACT

A wealth of period literature from as early as 1856 through the 1920s promoted the toning of salted paper prints with platinum to achieve certain aesthetic effects and improve silver image permanence. A variety of toning bath compositions were proposed to achieve a range of image tones. Additionally, other platinum and matte silver photographic processes, such as kallitypes, silver-platinum prints (e.g., “Satista”), and silver-intensified platinum prints, were popular during the salted paper print revival and may have similar characteristics. However, few examples of prints containing both silver and platinum have been identified in museum collections. To investigate their chemical natures and range of appearances, the authors fabricated prints according to historic recipes. These simulacra were analyzed by XRF spectroscopy and color measurement and artificially aged to provide data relating to metal content, appearance, and longevity. High-resolution electron microscopy of the salted paper print samples revealed the chemical influence of the toning method on the metallic nanostructures that comprise the image. Ultimately, the analytical results are tied to visual observations to elucidate toning methods used by early photographers, contribute to process identification, and draw conclusions about the conservation of these materials.

摘要

早在1856年至1920年代的大量时期文献中就促进了用铂对盐纸印刷品的色调调整，以达到一定的美学效果并提高银质图像的持久性。提出了各种调色浴组合物以实现一定范围的图像色调。另外，在盐纸印刷版复兴期间，其他的铂和哑银照相工艺（例如kallitypes，银-铂印刷版（例如“ Satista”）和银增强的铂印刷版）很受欢迎，并且可能具有相似的特征。但是，博物馆藏品中几乎没有发现包含银和铂的版画实例。为了研究其化学性质和外观范围，作者根据历史配方制作了版画。这些模拟物通过XRF光谱和颜色测量进行了分析，并进行人工时效处理，以提供与金属含量，外观和寿命有关的数据。盐纸打印样品的高分辨率电子显微镜揭示了调色方法对构成图像的金属纳米结构的化学影响。最终，分析结果与视觉观察联系在一起，以阐明早期摄影师使用的调色方法，有助于过程识别，并得出关于这些材料保存的结论。