300,000 PICTURE A MINUTE.

Hokitika Guardian, 12 November 1925, Page 2

300,000 PICTURE A MINUTE.

LONDON. Aug. 11. In the private kineina theatre of Messrs Vickers. Ltd.. a reporter was yesterday shown a lilm taken by a new camera, which is capable ol recording pictures at the rate of 1100,000 a minute. The human eye cannot receive more than 30 impressions in a second; tlie new camera is more than 150 times as speedy, enabling any detail which escapes to eye to lie analysed when Lhe finished film is shown m slow motion. The pictures shown yesterday included one of the bursting of a glass glolxj by a charge of powder, each minute particle of glass being seen to move as though lightly blown outwards from the centre. The only camera of this type In existence is owned by the lirilish Govenmieiit. and is being used in the study of the effect of armour-piercing shells on different kinds ol steel plate. The construction of the camera which weighs four tons and cost £15.001. occupied four years. Forty lenses, mounted on a revolving disc come in turn liefore the camera aperture, the disc itself revolving 1-5 times in a second. The actual time ol exposure for each picture taken is l-GO.OOOth of a second. Heliiml tile alKUtiire a highly sensitised film revolves round a drum at the rate of 18.000 feet ;>or second. One of the chief problems that had vo he solved beoro the machine could lie used was how to keep the film on the drum at this great speed. The solution was found by piercing the drum with a series of small holes and placing an apparatus which sucks the film on to the drum. An intense light is necessary to allow pictures to bo taken at very high sliced. and problems in tins re-