A radiation image read-out method and apparatus for a stimulable phosphor sheet, provided with a layer of stimulable phosphor, which has been exposed to radiation to carry information about an image, and the image is thereby stored on the stimulable phosphor sheet. The method includes the steps of: exposing the stimulable phosphor sheet to stimulating rays to emit light in proportion to the amount of energy stored thereon during its exposure to radiation; sensing the emitted light to generate a detection signal; amplifying the detection signal using a first amplifier or a second amplifier, dependent on the magnitude of the detection signal, to generate an amplified detection signal, the first amplifier differing from the second amplifier; and converting the amplified detection signals into a digital signal to form a digital image. In a preferred embodiment, the first and second amplifiers are logarithmic and linear amplifiers.