How were photos processed after a user finished a roll of film in the Brownie?
Answer
By mailing the entire camera back to Kodak
To fulfill the promise of simple picture-making, the user was not required to perform any technical tasks such as developing negatives or making prints. After the film was exposed, the entire camera unit was mailed back to Kodak. The company then handled the film processing and printing, returning the finished images to the customer and often reloading the camera, which completely outsourced the technical challenges of the era.

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