New Method of Developing Roll Films
By T. B. LAMBERT
Many devices have been made for developing and fixing roll films. There is the simple wholesale method of the professional who hangs a weight on one end of the film and lets it down in a deep tank of developing fluid where it hangs submerged from an upper support until the development is complete. Then the support, the film, and attached weight are removed, dipped into a similar tank of running water, then to another tank of fixing solution, and subsequently washed and dried.
This is the only practical plan where there are many such films to be handled simultaneously, but the amateur who has only one or two rolls a week cannot afford the tanks, the space, nor the expense incident to such a method. The film is usually drawn back and forth through a developing solution placed in a tray, and after the development has proceeded far enough, the same process used in washing, then the hypo solution, and finally through the last washing for about 20 minutes, all making a tedious process.
Some amateurs and a few professionals who but occasionally develop roll film use a mechanical device that rolls the film into a light-proof package which is inserted in a metal tank for development and subsequent fixation. This is a standard process, the apparatus being on sale at all supply houses, but it has its drawbacks.
An Ordinary Drinking Glass Used for Developing Roll Films
The following method is not only simple but perfect in its operation and requires no special apparatus, only a tumbler or lemonade glass, and an ordinary lead pencil for its operation. A glass rod is preferable to the lead pencil, and it is also convenient to have a deep tin cup, or similar device, to cover up the lemonade glass and make it light-proof, should it be desirable to turn on the white light in the dark room.
Pour enough developing solution into the glass tumbler to cover completely the roll of film when it is standing on end. In the dark room open the film roll, remove the backing paper and the paper ends on the film, run it through clear water until it is thoroughly and uniformly wetted from end to end, and drop it endwise into the tumbler of developer. Immediately insert the pencil or glass rod into the center of the roll, and with a rather quick circular motion, move the rod around so that it will quickly pass between the several convolutions of the film and thus distribute the developer all over its surface. Repeat this operation at once, then again in a few seconds, then in 15 or 20 seconds, then in 30 seconds, then in 1 minute, and so on, with greater intervals of time. If a 20-minute developer is used, it will only be necessary, at the latter part of the development, to separate the layers every 2 or 3 minutes.
When the development is complete, pour off the solution and rinse in the same glass by letting water run through it while passing the pencil or glass rod between the layers several times. The water may then be drained off, and the glass filled with the fixing solution. While the film is fixing, the glass rod should be passed between the layers several times to renew the solution in contact with the film.