Latent image fading

Appelton TC. Resolving power, sensitivity and latent image fading of soluble-compound autoradiographs. J Histochem Cytochem 1966 14 414. 

Boren, HG., Wright, EC, Harris, CC. Quantitative light microscopic autoradiography. Emulsion sensitivity and latent image fading. J Histochem Cytochem 1975 23 901-909. 

Figure 1. The lowest vacant electronic energy level (n,) and the highest occupied one (c, ) of dyes as correlated with the appearance of the light-induced ESR signal, desensitization, and latent image fading by the corresponding dyes.

While the memory effect of the developed film is almost infinite, this is not the case for the latent image which slowly fades, depending on the number of originally activated silver atoms, the film type and external conditions like temperature, humidity, etc. When stored under ambient conditions, about 80% of the latent image disappears in half a year. 

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