= Objects with !StackDetections with Multiple ippObjID = Peder noticed that not all StackDetections for a given psps object have the same ippObjID. This is expected and is also true for single frame detections. A one to one correspondence between ipp object (dvo average) and psps object is not guaranteed. Object.ippObjID gives the ipp object that supplied the average properties. Any detections for the object that have a different ippObjID were not included in the average calculations. These are primarily very faint detections many are from forced photometry. In SAS 11 PSPS objects with stack detections from multiple dvo objects appear to be *all* bad objects. A query for objects which have detections with more than one ippObjectID and any of xFlags != 0 returned no rows {{{ select Top 10 o.objID, count(distinct sd.ippObjID) INTO mydb.[funnyobjs2] FROM Object as o join StackDetectionFull as sd on o.objID = sd.objID WHERE o.rFlags != 0 or o.gFlags != 0 or o.iFlags != 0 or o.zFlags != 0 or o.yFlags != 0 or o.qualityFlag & 16 != 0 GROUP BY o.objID HAVING count(distinct sd.ippObjID) > 1 }}} A similar query using Detection instead of StackDetection did find some objects with multiple dvo objects and non-zero flags How does this happen? {{{ Example from SAS 11 ----------------------- 107513365582181356 was the result of 4 garbage detections within the region for the given ID DVO has 7 detections with this objID Staticsky run for skycell.1316.093 found a i=18 and a r=22 detection on artifacts. Since there are detections in two filters forced detections were created in the other 3 filters Call these detection group 1 Staticsky run for skycell.1316.083 found 2 detections on in r on another artifact near the coordinates and nothing in the other filters Call these detection groups 2 and 3 DVO associated the g, i, z, and y detections from group 1 with the r band detection in group 3 into one dvo object Call this object A and DVO associated the r band detection from groups 1 and 2 with a second DVO object call this object B Both dvo objects have the same PSPS objID PSPS has 6 detections. The r band detection from object A was dropped by ippToPSPS Could this be because it doesn't like two detections for the same PSPS object in the same cmf file? }}}