  Collaborating across dissimilar, distributed spaces presents numerous
challenges for computer-aided spatial communication. Mixed reality (MR) can
blend selected surfaces, allowing collaborators to work in blended f-formations
(facing formations), even when their workstations are physically misaligned.
Since collaboration often involves more than just participant pairs, this
research examines how we might scale MR experiences for large-group
collaboration. To do so, this study recruited collaboration designers (CDs) to
evaluate and reimagine MR for large-scale collaboration. These CDs were engaged
in a four-part user study that involved a technology probe, a semi-structured
interview, a speculative low-fidelity prototyping activity and a validation
session. The outcomes of this paper contribute (1) a set of collaboration
design principles to inspire future computer-supported collaborative work, (2)
eight collaboration patterns for blended f-formations and collaboration at
scale and (3) theoretical implications for f-formations and space-place
relationships. As a result, this work creates a blueprint for scaling
collaboration across distributed spaces.
