Changes to camera geometry affects application of calibrations

calibration
obs_lsst
Tags: #<Tag:0x00007f61ab919498> #<Tag:0x00007f61ab919330>

(Simon Krughoff) #1

DM-22605 fixed the way both types of sensors are assembled so that the data management camera geometry is consistent with the camera construction engineering diagrams. This was intended to be transparent to end users, however there is a side effect that some types of calibrations constructed with the old geometry cannot be applied using a stack that includes these changes.

Weekly build 11 is the first build to included the changes from DM-22605, so any calibrations produced with builds before that build should not be applied with weekly 11 or later. The safest thing to do is to make new calibration products with a newer stack if reduction is intended with a newer stack.

Apologies for not publicizing this more widely before. I hope that most are not too affected since it seems like a standard practice is to produce calibration products and do the data reduction at essentially the same time.


(Paul Price) #2

Is this for all cameras, or only LSST?


(Simon Krughoff) #3

Sorry. This is only cameras supplied by obs_lsst. Other instruments are unaffected.


(Merlin) #4

Also worth noting that this will apply to anything done in pixel coordinates, so it’s not just image-like things, but also defects, for example.