An exposing apparatus including a conveying device, a scanning device and an exposure device. The conveying device conveys a photographic film reciprocatingly during a first stroke and a second stroke opposite to the first stroke. The scanning device scans an image on the photographic film with light during one of the first stroke and the second stroke, and forms at least one of light reflected from the photographic film and light transmitted through the photographic film into line-shaped image light. And the exposing device exposes a light sensitive material to the line-shaped image light while conveying the light sensitive material relative to the line-shaped image light. The conveying device, moreover, conveys the photographic film at a first conveying speed when the light sensitive material is not exposed to the line-shaped image light, and conveys the photographic film at a second conveying speed when the light sensitive material is exposed to the line-shaped image light, with the first conveying speed being faster than the second conveying speed.