Adding weights, and firmware updates

ArduCopter
1

Hello ,
I have two questions
1)shall Ido all the process of tunning whenever I add a bit of weight to my copter?

isn’t there any way to upgrade the weight for the copter and it learns it by it self ?

  1. after Updating a new firmware , should I do the tuning process and fly again to get the hover throttle learned before flying in the alt hold mode or AUTO mode ?
2

Do the setup and autotune with minimal weight then add you DSLR/sprayer/whatever.
Should only need to retune if you significantly change props, motors or arm length.