There are no small numbers of culturally invaluable negatives not accompanying their prints. In this article, assuming a usage of the contemporary printing process, the author introduces examples of the practical use of those negatives both within the country and abroad, discusses its importance in photographic conservation and a task for the future.

Beginning in September 2018, I had the opportunity to research the Art Institute of Chicago's management of its photography collection, and its current techniques of photographic conservation, for a period of six months. During the same period, I also undertook training at the museum's departments of Photography, Conservation and Science, and Registration.

In this paper, by referring to deterioration factors of photographic images, I will introduce some examples of actual conservation treatments at the Art Institute of Chicago. Furthermore, I will report on the environmental conditions and the history of cold storage for photographic collection at the museum, which it introduced in 1982 - the first art museum in the world to do so. I will also describe the typical practices of a photograph conservator at the institute.

“Guidelines for preserving photographs of cultural properties” issued in 2012 has been playing a role to warn against the risk of lost on digital photographic images and indicate guides on measures. However due to subsequent techno logical progress and changes in the situation, update of the contents have come to be needed. Since we are currently in the process of deliberation the revisions, here is an overview. The outline of this guideline and the contents expected to be updated are explained.

Using paper materials as an example, the reproducibility of colors will be explained based on the color difference of the color chart, and digitization methods based on color adjustment will be introduced using flatbed scanners and digital cameras as examples.

Spectra of color in motion picture film were measured. The spectra were reproduced from scanned data based on principle component analysis. Taking projection condition into consideration, authentic reproduction of color in film is performed using the reproduced spectra.

As a means to inheritance art to the future, preservation and restoration of the art itself, duplication, reproduction, replay, and recording with images and videos are performed. I will give an overview of these art interventions in comparison with the philosophy and methods of conservation for cultural property in Japan. Absolutely, does art have to be preserved?

This paper described a diagnosis system that evaluated deterioration states of photographic films of which the base material was composed of triacetyl cellulose (TAC). The concept of this diagnosis system is based on that of a thorough medical checkup. This diagnosis system provides knowledge on not only the amount of acetic acid gas generated from TAC-based films, but also the structure and physical properties of TAC-based films. From the results obtained from multiple analytical apparatuses, quantitative and comprehensive deterioration diagnosis of TAC-based films was achieved. In addition, by applying this diagnostic system, even for TAC-based films in which no indications of deterioration were observed by visual and olfactory inspection, the deterioration state of TAC base could be distinguished.

Photography based on photoreduction and printing based on photocuring had developed while interacting with each other, and had established the graphic arts field. In printing, typographical information and photographic images were integrated by an optical halftone dot forming technique. It became a standard method by using a contact screen and a lithographic film for plate making. Furthermore, pre-sensitized PS printing plates of industrial products had made a full-scale transition from graphic-arts to graphic-systems. Digitization in the field of plate making has progressed by reading images with a scanner and outputting digital halftone dots after Desk Top Publishing DTP editing. After about 30 years of the advent of the scanner, filmless has been achieved by a plate setter that draws directly on the Computer To Plate CTP with laser beam.

Au nanoparticles were immobilized on glass plate with ITO film by pulsed electrolysis. Using the product (Au-ITO) as an electrode, an electrochemical polymerization of pyrrole was carried out by continuous potential sweeps, and the  polymerization process was compared with that on an untreated ITO electrode (ITO).  As a result, it was confirmed that the oxidation of pyrrole on Au-ITO electrode occurred at more negative potential (at least 200 mV) than that on ITO electrode.  It was also found that the use of Au-ITO can suppress the electrochemical deactivation of the polypyrrole during the polymerization.