Keep track of BRIGHT in final coadd mask, keep ormask

[esheldon]

keep track of BRIGHT in the coadd_exp.mask

This coadding mask is currently only being set for EDGE and if it is set
it is considered a bug and raises an exception.  Also add in BRIGHT and
SAT anywhere BRIGHT was set in the warps.  The SAT will prevent
detection in those areas

Updated interp flags to include BRIGHT as it is now required to be added
to the mask plane by the caller.  No longer setting SAT for BRIGHT
at that stage

added verification that EDGE and NO_DATA are not set in the warps

added verification that EDGE is not in the coadd

corrected some typos

[esheldon]

I'm currently setting the observation ormask to the exposure mask, and leaving bmask as zeros

I don't think this is actually used downstream, only the exp.mask is used, but might want to be consistent with DES here.

@beckermr what do you recommend?

[beckermr]

My recommendation is the following:

1. Compute an OR of all of the flags from the SE input images and put this in the ormask.
2. For the bit mask of the coadd, send in a mask that has flags for interpolated pixels and bright pixels.

[esheldon]

Then the mask in the exposure would not map to either the obs.bmask or obs.ormask which could be confusing

[beckermr]

Indeed it could be, but I think these masks are the most sensible. The OR mask has data about the inputs to the coadd. The bmask has data about how the coadd was processed in each pixel.

[esheldon]

now I'm not sure why we want 2 separate from 1 since it is a subset

[beckermr]

That's true. We could store them in the same set of bits.

[esheldon]

How about this:

Do 1. as you said for ormask, but make bmask a copy of the mask in the exposure

[beckermr]

Yep. We should keep ormask flags for which pixels got inteprolated too.

[esheldon]

Do you mean define a new mask plane to propagate?

[esheldon]

We could re-use INTERP

but then we would not be able to distinguish between things we interpolated and the stack interpolated, which may be useful especially since with real images both may be happening

[esheldon]

But this would in any case be redundant with the ormask, which is propagating whatever we would have labeled as interpolated

[esheldon]

is this ok to merge?

[beckermr]

Did you want to add the CATSIM download the CI job? Happy to do that in another PR too.

[esheldon]

thanks, let's do it in a different PR