  "Scene description" applications that describe visual content in a photo are
useful daily tools for blind and low vision (BLV) people. Researchers have
studied their use, but they have only explored those that leverage remote
sighted assistants; little is known about applications that use AI to generate
their descriptions. Thus, to investigate their use cases, we conducted a
two-week diary study where 16 BLV participants used an AI-powered scene
description application we designed. Through their diary entries and follow-up
interviews, users shared their information goals and assessments of the visual
descriptions they received. We analyzed the entries and found frequent use
cases, such as identifying visual features of known objects, and surprising
ones, such as avoiding contact with dangerous objects. We also found users
scored the descriptions relatively low on average, 2.76 out of 5 (SD=1.49) for
satisfaction and 2.43 out of 4 (SD=1.16) for trust, showing that descriptions
still need significant improvements to deliver satisfying and trustworthy
experiences. We discuss future opportunities for AI as it becomes a more
powerful accessibility tool for BLV users.
