The tenantId on a PhotoRecord ties every catalogued photograph to a single owning organization, which is how Relic keeps one dig company's photos from ever appearing alongside another's. You will rarely set this field by hand — it is filled in automatically from your active session when a PhotoRecord is created. It is the value Relic filters on whenever it lists, searches, or counts photographs, and it is indexed so those lookups stay fast even with large photo libraries.
Technical section
Data model, API, and internals — visible to developers.