Hi Grey,
Thanks for the reply. I'm not an expert programmer or dev (I only casually learned Python) however with regards to dive computers not supplying that info, I see a couple of (in my opinion) easy workarounds to this.
1: If the DC does not provide End SurfGF, then this field can be set to null (blank).
2: If the DC does not provide End SurfGF, then this can be calculated by Subsurface based on the dive profile information supplied by the DC
3: Regardless of if the DC provides the info or not, Subsurface could calculate the end SurfGF based on the dive profile information supplied by the DC, overriding whatever end SurfGF the DC provides.
4: Have an option in Subsurface to enable a calculated end SurfGF in addition to data from the DC.
Noting the end SurfGF manually in the notes is an option but does not allow us to easily visualise multiple dive's end SurfGF at the same time to compare / browse, nor does it allow us to sort the dives based on this important info. The same goes for the surface interval request to be added to the list of available columns.
I didn't realise Stepfen had already requested this feature, great minds think alike :)
I'm more than happy to help out testing these new features, I have access to Shearwater and Garmin (my primary / backup computers) and can easily ask friends for log files from their non SurfGF capable computers or RGBM etc..
Let me know.