I spent the last few days traveling; hence the lack of posts. The postable work includes figuring out the most robust methodology for associating nod-and-shuffle spectra in the PRIMUS 2d images with entries in the file used by the milling machine to cut the masks, and simultaneously figuring out which holes in the mask are primary and which are secondary, etc.
I also figured out what might be a fast and robust way to find and fit the satellite trails in calibrated astronomical images. Time to register "satellitetrail.net"! Along the same lines, I also worked on the fitting and subtraction of what in SDSS data are known as "filter reflections"—glare we get because the filter edges get exposed to the light of stars outside but near the field.