refuse to create a data collection until at least some of it's raw files exist
refuse to create a data collection until at least some of it's raw files exist

DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb