The Digital Panopticon will assemble a larger collection of datasets than any other crime history project to date (including, amongst many others, the Old Bailey Proceedings, convict transportation registers and prison records), covering hundreds of thousands of individuals. To effectively bring together this information to reconstruct the lives of offenders, we need to develop a detailed understanding of our datasets – of what information is and isn’t recorded on offenders, and how this varied both over time and across different sets of records. Traditional methods of data analysis and representation such as manual counting and tables are inadequate to this end. This paper instead highlights the power of digital technologies in identifying previously unrecognised (and otherwise unrecognisable) patterns. The techniques of data visualisation in particular have been invaluable in uncovering how extensively, and in what manner, information on offender age, occupation and crime location was recorded within our sources. By using digital technologies to step back from our datasets, and see them in their entirety, we can develop a much fuller and more systematic understanding of the sources we are working with.