In this study I examine the use of visualization within everyday research practices in computational physics. In doing so, I attempt to move from the well documented representational issues elicited by the concept of the image, to more microscale issues of the habitual structuring of the everyday that emerge when a specific example of science in the making is analysed. To this end, I focus on one specific example, of tracing a computational error through a fluid dynamics simulation of the 'lock exchange' experiment. This simulation is one small part of the research that goes on within one of Europe's largest computational physics research groups, the Applied Modelling and Computation Group at Imperial College in London, where I am involved in ongoing ethnographic fieldwork research. Visualization is shown to play a central role, not just in daily routines of investigation and problem solving, but in the process of habituation through which scientists cultivate the dispositions through which everyday life gains its texture and form. Far from being a detachable representation of a part of a world, simulation is shown to come into being as a process within a world structured by the repetitions and improvizations that characterize research practice.