Data quality

General approach to validate the reductions of SPHERE data

The first release of IRDIS and IFS data (in PUBLIC_reduced_science_OLDRELEASE_1) did not include a validation step of all outputs. For the new release (IRDIS, IFS, ZIMPOL, see algorithm page), the quality of the reduction is visually checked based on the final stacked no-ADI image. When re-reduced after a detetection of a problem (for example centering issue or use of bad dark files), the files are not available. However, data with unsolvable observation problems (for example an open AO loop) are visible in public workspace when requesting from the client but flagued () to indicate the reasons for the lack of good reduction for such data. Only the un-flagued validated data are transfered to the DIVA+ archive.

Particular case of the SHINE survey

The SHINE suvery data (observed by the SPHERE consortium for a large part of the GTO) were reduced with similar algorithms (except for the additional characterisation step) to the other data in 2015-2022, but the consortium team performed specific validation steps. The first release of the SHINE survey (F150, first sample of targets) is described in Desidera et al 2021, Langlois et al 2021, and Vigan et al. 2023. It is currently only available on our DIVA+ portal and correspond to the data used in these publications. The full data set will soon also be available.