The primary purpose of this research is to gain understanding into the processes of knowledge construction and the underlying epistemic practices and assumptions of media preservationists working in the artisanal mode of preservation to produce digital manifestations of complex visual documents, specifically analog video recordings. It focuses on "artisanal digital reformatting" in institutional sites of small-scale, high-skilled digital copying. This dissertation research studied 13 media preservationists (eight digitizers, four administrators, one quality control specialist) recruited from six preservation labs. Data were generated in the form of discourses and observations of material practices by conducting semi-structured interviews, video-recorded observations, and review sessions in which participants reflected on the video-recordings of their workplace practices. Data were analyzed using qualitative-interpretive methods, including discourse analysis and interpretive phenomenological analysis. The findings of this research suggest that artisanal digital reformatting is an interpretive act of visual translation that unfolds within epistemological, phenomenological and cultural dimensions of participants' workplace practices. This work blends "mental and manual" dimensions of technical labor in which participants incorporate their trained vision, embodied judgment and historical knowledge to detect and diagnose typified visual errors to produce "legitimate" digital copies. Participants identify tensions between trust, credibility and the applicability of new practical knowledge as it circulates across three zones of knowledge construction in the context of their situated activities: personal, institutional and community zones of knowledge. Analysis of digitizers' moral commitments to archival imperatives and their efforts to enact them in practice suggests that normative considerations operate alongside the practical requirements of digital copying. Through an analysis of participants' practices and discourses, a coordinated array of epistemic techniques and visual practices were identified. This research analyzed the experiences of digitizers carrying out their work to understand how they train their perceptions as well as the affective dimensions of their work. This research then considered how participants integrate knowledge from the wider occupational community of media preservationists into digitization work. Finally, this research explored how normative aspects of practice shape the construction of knowledge, by analyzing participants' moral commitments to archival imperatives and their efforts to enact those commitments in practice.