So I'm coding up a MIDI controller where I'm using capacitive touch on a Teensy 3.2 and I want to try to maximize the range/output I'm getting with this. At the moment I'm, roughly, getting a range of ~1000 to ~6000. I want to build in a calibration routine where I can store the range in the EEPROM so it is fixed on startup, but I want to know what this range is impacted by. Is it just a byproduct of the circuit/wiring, or will it vary a lot by location (in a different house/place), power (different computer/USB powering), etc...

As in, can/should I create a calibration routine where I fix the min/max to scale it with in the EEPROM or do I have to do this "per use" basically as it will vary a ton?