The room temperature oxidation of metals and organic materials can be detected photographically (the Russell Effect). Flat objects are specially suited to the technique and several types of object have been examined. Information can be obtained on changes made to objects if these alter the rate of oxidation. Several applications are considered, detection of recent abrasions on metals, watermark detection, testing storage materials for hydrogen peroxide evolution, finding areas on an object that have been chemically treated, distinguishing between old and newly applied oil paint and testing conservation methods.