The sizeBytes field records how large a PhotoRecord's image file is, measured in bytes — so a 4 MB camera photo would store roughly 4,000,000 here. Relic captures this at upload time so it can display file sizes in the catalogue, warn about unusually large images, and help estimate storage use across a project's photo library. Unlike the text-based file fields, this is a whole-number value, and together with filename, filePath, and mimeType it completes the description of the stored image.
Technical section
Data model, API, and internals — visible to developers.