Which of the following is not used to turn a roll of film into negatives?
fixer
enlarger
developing tank
acid bath

The correct answer is Enlarger

Explanation:

To turn a roll of film into negative is divided into three processes:

Exposure:

This process is inside the camera when the film is rolled inside the development tank. The empty photographic film, composed by a plastic base associated with gelatin emulsion, gets exposed to some right amount of light. In this phase, we’re unable to see the image. Here, the film must not be exposed to natural or artificial light, while it’s been unrolled from the tank.

Chemical Process:

After that, the film is taken to the Developer Bath, when it’s bathe with a mixture of compounds. To stop reactions, it’s applied acetic acid and then the film is bathed again with ammonium thiosulfate, which will be used to fix the image. This process is made inside the lightproof tank.

Refinement Process:

With the lights on, the film is washed with water and a wetting agent. This last bath will remove the fixer and the hard watermarks. Afterward, the film will be dried in a dust-free environment. Only after passing through these three processes, the image gets permanent and making the negative light-resistant.

The enlarger is the equipment responsible to turn the negative into larger paper photography. It’s a box with a light inside, that will project the inverted image of the negative to another lens. This lens will reverse the projected image on a photosensitive paper.  

This is the last step to print a photo. Recently, the digital photography has changed the print steps. The development tank was substituted by digital devices that contain images in pixels, making this process relied on computers.

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