7 CONCLUSIONS

The formation of silver-mirroring edge patterns on both single-glass and stacked-glass negatives can be understood as being the result of a gas diffusion and reaction mechanism. Incubation chamber experiments show that, in the absence of ventilation, edge patterns can also arise on single-glass negatives. For stacked-glass negatives, local variations of the inward extension of silver mirroring are correlated to the local distance between the plates. Visual characteristics of edge profiles indicate that reaction mechanisms involved do not obey simple first order reaction kinetics.