... I am still trying to determine the cause of a difference between the results for the new and old code with the other kernels. ... I then returned to trying to figure out the difference between the old and new drizzlepac coordinate mapping. It turns out the old drizzlepac was using its internal mapping code, so I forced it to use the wcs mapping code instead.But that did .. ... I did some more testing and code reading in drizzlepac in search of the discrepancy between the old an new version. ...