Two, and Why They Should Come From One File
Photographs taken in separate sittings are not identical.
The requirement for issuing or renewing the electronically-read passport lists two photographs on a white background, 35mm wide by 45mm tall — the consular pages write the pair as 45 × 35, height first, which is the same photograph described the other way round.
Print the same file twice. Two shots taken minutes apart differ in head angle and lighting, and 'identical' is doing real work in a requirement that a clerk checks by eye.