- Email: [email protected]
Handling cine film at high temperatures
264
]V~ASTMAN KODAK COMPANY NOTES.
[.I.F.I.
H A N D L I N G CINE FILM AT HIGH T E M P E R A T U R E S ? By J. I. Crabtree.
INFORMATION is given relative to the storage, shipment and conditioning of motion picture film before and after exposure, and the processing of film at high temperatures. Two methods of drying film are described whereby the loosely wound film is placed in a container ( I ) with dried paper, which absorbs the moisture, or (2) with some deliquescent chemical such as calcium chloride. For high-temperature processing, three methods of preventing excessive swelling of the gelatin are described: (A) By the use of concentrated solutions; (B) by the addition of inactive salts, such as sulphates or phosphates, to the developer solutions; (C) by permanently hardening the gelatin. For hardening, alums are preferred to formalin, as the latter gives trouble from fog and objectionable odors. Chrome alum yields maximum hardening when used as an intermediate bath between development and fixation. When incorporated in a fixing bath, chrome alum rapidly loses its hardening properties. Procedures are recommended for processing motion picture film at 85 ° F. and at 9°0 F. In the former, three to four minutes' development in a concentrated developer is recommended, followed by a few seconds' water rinse and three minutes' immersion with agitation in a 3 per cent. potassium chrome alum solution. Any hardening or ~aon-hardening fixing bath may be used after treatment in the chrome alum hardening solution. Washing should be completed in ten to fifteen minutes. For processing at 9 °0 F. the same procedure is used, except that the chrome alum hardener contains 12 per cent. sodium sulphate in addition to the chrome alum. Films processed by these methods will dry comparatively rapidly, as excessive swelling which makes drying slow and difficult will have been prevented. Several miscellaneous hints are given in conclusion relative to the wearing qualities of film processed by the methods suggested, the decomposition of films with age, and ways of avoiding brittleness. Communication No. 218 from the Research Laboratories of the Eastman Kodak Company and published in Amer. Cinemat.. 5:4, 1924; Amer. Phot., I9:36, 1924; B. J. Phot., 71:762, I924; Trans. Soc. Mot. Pict. Eng., No. 19, I924.
]V~ASTMAN KODAK COMPANY NOTES.
[.I.F.I.
H A N D L I N G CINE FILM AT HIGH T E M P E R A T U R E S ? By J. I. Crabtree.
INFORMATION is given relative to the storage, shipment and conditioning of motion picture film before and after exposure, and the processing of film at high temperatures. Two methods of drying film are described whereby the loosely wound film is placed in a container ( I ) with dried paper, which absorbs the moisture, or (2) with some deliquescent chemical such as calcium chloride. For high-temperature processing, three methods of preventing excessive swelling of the gelatin are described: (A) By the use of concentrated solutions; (B) by the addition of inactive salts, such as sulphates or phosphates, to the developer solutions; (C) by permanently hardening the gelatin. For hardening, alums are preferred to formalin, as the latter gives trouble from fog and objectionable odors. Chrome alum yields maximum hardening when used as an intermediate bath between development and fixation. When incorporated in a fixing bath, chrome alum rapidly loses its hardening properties. Procedures are recommended for processing motion picture film at 85 ° F. and at 9°0 F. In the former, three to four minutes' development in a concentrated developer is recommended, followed by a few seconds' water rinse and three minutes' immersion with agitation in a 3 per cent. potassium chrome alum solution. Any hardening or ~aon-hardening fixing bath may be used after treatment in the chrome alum hardening solution. Washing should be completed in ten to fifteen minutes. For processing at 9 °0 F. the same procedure is used, except that the chrome alum hardener contains 12 per cent. sodium sulphate in addition to the chrome alum. Films processed by these methods will dry comparatively rapidly, as excessive swelling which makes drying slow and difficult will have been prevented. Several miscellaneous hints are given in conclusion relative to the wearing qualities of film processed by the methods suggested, the decomposition of films with age, and ways of avoiding brittleness. Communication No. 218 from the Research Laboratories of the Eastman Kodak Company and published in Amer. Cinemat.. 5:4, 1924; Amer. Phot., I9:36, 1924; B. J. Phot., 71:762, I924; Trans. Soc. Mot. Pict. Eng., No. 19, I924.