the problem is:
if you look at the pictures carefully,
the value should reach the lowest and highest maximum number: 0 and 4096.

it does when I move the joystick in the beginning,
just after calibrating,


but after just a few moves,

the lowest and highest value start to diminish for some unknown reason.

If I unplug and replug the usb or restart, then calibrating it,
it is good again,
but after I move the stick some more, then the value start to diminish again.

Is this a bug?
I hope mega_mozg can clarify this.