Photostress recovery time (PSRT) has frequently been used as a quantitative measure of macular function. Initially described by Magder' as a clinically useful tool for following the progression of central serous retinopathy, photostress recovery has also been utilised in the study of the ocular toxicity of antimalarial medications,2 ocular toxicity of birth control pills,3 and various macular and optic nerve diseases."7 Although a precise pathophysiological explanation for aberrant photostress responses has yet to be offered, it has been clearly demonstrated that optic nerve and macular disease can be differentiated on the basis of PSRT, where the retina with macular disease has an increased recovery time and that with optic nerve disease has a normal recovery time.7A major criticism of photostress recovery testing has been the lack of a standardised technique in conducting the test. The test consists in measuring the visual acuity of a given eye, illuminating that eye with a high intensity light for a specific length of time-creating a central scotoma-and measuring *Deceased.