Shadowgraph and schlieren methods have served to image shock waves for almost 150 years, but the traditional field-of-view of these instruments is often too small for large-scale experiments. On the other hand, optical methods to reveal shock waves in the field (e.g. background distortion and sunlight shadowgraphy) are often crude and weather-dependent. Between these extremes lie some useful but little-used optical approaches for large fields-of-view, two of which are exemplified here.