How do i get variable data from outside a callback function scope?

Question

I'm trying to get the values of the current position of the range slider, so as to put in an object for my ajax request...

let minPrice;
let maxPrice;
$('.range-slider').on('start', function(input) {
   minPrice = input.from;
   maxPrice = input.to;         
});       
console.log(minPrice,maxPrice);