Using the Gaia catalog is improving a lot the astrometry determination. The problem is that at the moment it is not possible to use a different catalog for astrometry and photometry, so getting a good astrometry is coming at the price of a poor photometry calibration. I know that UW is working in order to remove this restriction but in the mean time I am wondering if it would be possible to run the photometry calibration as a separate task once the calexps have been produced with processCcd and possibly using a different catalog ?
On top of solving my immediate problem, I think that having this possibility could also be very useful in general.