Being able to measure open circuit battery voltage is great, but it would also be useful to measure current while the light is running. That in turn can map to battery runtime and/or lumens. I wonder if any existing boards can do this, e.g. if they have adc pins connected to the relevant sense resistors. If not, it could be a cool feature in future boards.
Thanks, I do have a d4v2 but that’s a level of modding that I wouldn’t want to do for this. I s hoping enough capability might already be in the hardware, to make accessing it into a matter of programming. Maybe I’ll just go with lux measurements.