Transient use of information visualization may support specific tasks without permanently changing the user
interface. Transient visualizations provide immediate and transient use of information visualization close to
and in the context of the user’s focus of attention. Little is known, however, about the benefits and limitations
of transient visualizations. We describe an experiment that compares the usability of a fisheye view that
participants could call up temporarily, a permanent fisheye view, and a linear view: all interfaces gave
access to source code in the editor of a widespread programming environment. Fourteen participants performed
varied tasks involving navigation and understanding of source code. Participants used the three
interfaces for between four and six hours in all. Time and accuracy measures were inconclusive, but subjective
data showed a preference for the permanent fisheye view. We analyse interaction data to compare how
participants used the interfaces and to understand why the transient interface was not preferred. We conclude
by discussing seamless integration of fisheye views in existing user interfaces and future work on
transient visualizations.