Highly exposed radiographs are utilized in microradiography in order to increase the signal‐to‐noise ratio. Relief radiography enables the evaluation of these microradiographs. Relief‐exposure characteristics are shown to follow a relationship of the typeR=Rm[1−exp(−E/Em)], whereRis the relief height,Eis the exposure, andRmandEmare constants. The density of developed silver in Ilford L‐4 nuclear emulsion is found from the value ofRmto be 2.86. The constantEmis shown to give the exposure for maximum contrast. The experimental results are discussed and compared to those found in the literature.