Advances in image synthesis techniques allow us to simulate the distribution of light energy in a scene with great precision. Unfortunately, this does not ensure that the displayed image will have a high fidelity visual appearance. Reasons for this include the limited dynamic range of displays, any residual shortcomings of the rendering process, and the extent to which human vision encodes such departures from perfect physical realism. Image quality metrics are paramount to provide quantitative data on the fidelity of rendered images. This course addresses techniques to compare real and synthetic images, identify important visual system characteristics and help reduce rendering times significantly. Case studies involving both static and dynamic images are considered. Their different image quality metric requirements are compared and contrasted.