Is my source in Rec.709 or DCI XYZ color space?

The color space of commonly used digital image files is RGB (Rec.709). Therefore, this is the default selection in QMX. If however, the source's color space has been converted to the Digital Cinema XYZ, during the post-production process and prior to bringing the files to QMX, then the selection must be set to DCI XYZ in QubeMaster Xpress.