LIFE OF FILMS

Hokitika Guardian, 7 November 1930, Page 5

LIFE OF FILMS

HUMIDITY CHIEF FACTOR. 1

Photographic films' may last for

thirty years, or they may last for a month. The question is one about which there can be no fixed rule, it was learned yesterday, but the news that Andree’s films have been successfully developed-after having been lying amid the snow for thirty years lias caused no surprise to those connected with the film business,

Humidity is the biggest factor in the life of a film, said the: manager of one photographic supplies firm. Films used in the tropics would probably not. keep more than a month after exposure, while one kept in ,a dry, cold atmosphere, such as in the Arctic of Antarctic, might be good for many years. “You can bet your life that had Andree crashed in a tropical jungle there would not have been much left of his films in a month,” he said. It was generally considered that the emulsion did not keep as well on films as on plates, and he had had experience of plates which were seventeen years old being successfully developed,

One of the difficulties that occurred in modern films was the fact that they had been made to work much faster than the films of twenty years ago. It had been found, he added, that the faster the film the poorer its keepin qualities. •>,- ■ Gelatine is used extensively in making films and.it was found on developing films that had been used in the tropics such as on a ship travelling from England to New Zealand, that the

humidity caused the gelat ne to swell and that something like a fungoid growth occurred on the negatives. On the other hand, Arctic conditions would lie almost ideal.

I'rnct’Vally all the films sold in New Zealand bear a label giving the date by which they should be developed. This is usually about a year after the date of sale, but this does not indicate the probable length of the life of the film. Seven years is considered by one manufacturing firm to be a safe estimate of the time that the film will keep in good condition.