Hi, I've been trying out Gwyddion and pygwy for some automated data processing in our lab. So far, things are great and the examples have been really helpful (e.g., http://gwyddion.net/documentation/user-guide-en/pygwy.html) I have a similar need to the tutorial script - go through a bunch of files, flatten, get some statistics, and save PNG images. https://gist.github.com/ghutchis/bbfccd24898cd45be840954a3a6a14aa My problem is that I can see that the files have masks (i.e., for invalid points) but...