كيف يتم تحميل الكاميرات بالأفلام .. كتاب آلات التصوير

Chapter 3 - The mechanism of moving the film.

How are cameras loaded with films?

All film is photosensitive and should be kept in a dark place or in a light proof envelope. Rolls of film measuring 110 and 126 are impervious to light. Only the backing paper is exposed to light. But when the film is packed, the roll is dropped, the back is closed, and the roll is rolled until the movement stops. In this case, the number 1 appears on the back paper (which we see through the window behind the camera). The 120-gauge roll film also has a light-resistant backing paper (Fig. 8). To load this film into the camera, an empty spool or coil is placed in the take position, the new film is peeled off, and a few inches of the roll film is loosened. Then the tongue is placed in the slit of the coil or the empty spool. The complete bobbin is placed in place and then a driving mechanism is used to tighten the overhang. We should note that roll film cameras differ greatly, some of them require that the rewinding process be done until the arrows of the starting process are reached before closing the back cover of the camera, while others, especially the Rolleiflexes model, in which the film is moved between rolled cylinders to reveal its beginning and so on .

The 35mm cassette film differs from other films in that the cassette film does not contain a backing paper and needs to be rewound into its cassette after exposure and exposure. The rewinding button is lifted in the camera, then the cassette is placed in the place designated for it, then the film is pulled through it and its end is placed in the take-up coil (Fig. Moving The back cover is closed and then it is rolled on two frames to bypass the blurry area of ​​the film that occurred during the film packing.

How is the film moved the right amount between frames?

In older roll film cameras, the film was rolled until the next number appeared in the green or red window behind the camera. As for the new models, we find a form of automatic reconciliation. In cameras that are packed with a 126-inch coil, we find that each image frame of the film is marked with a hole for a single toothed wheel, and this hole is interlocked with a sensitive tool in the camera. In cameras measuring 35 mm, the toothed wheel rotates at a full rotation rate, i.e. an average of eight teeth between the image frames in film cameras. Automatic winding The stopping operation depends on the distance traveled by the toothed film moving handle

What does prevent double exposure and locked exposure mean?

Interlocked Most cameras with automatic frame alignment have a shutter-moving mechanism - the same movement is set for both. Thus, we find that it is not possible to release the shutter twice without moving the film. Likewise we find that it is not possible to wrap the film without first doing an edit
shutter .
On many 35mm cameras and roll film we find it
The mechanism can be enclosed for intentional double exposures