It has been understood that the nature of slurry discharge through a hydrocyclone underflow provides an indication of its performance. Although a few attempts have already been made to correlate the discharge profile with hydrocyclone performance in quantifiable terms, a user friendly, robust tool is yet to be developed. In this article an attempt has been made to measure the spray angle at various operating conditions using a simple photographic technique. The study is restricted to water only. The measured data thus generated has been correlated well with inlet Reynolds number and with two exit diameters. Good reproducibility of the measured data over a prolonged duration of time and the developed correlation reaffirms that the spray angle could possibly be used as a useful tool to monitor hydrocyclone performance. (C) 2013 Elsevier B.V. All rights reserved.