Automation Trigger Based on light brightness change

Configuration
1

I’m probably just over complicating this but, what’s the best way to trigger off of brightness change?

- alias: "Brightness - Master Bedroom Brightness Change (Device > Slider)"
    trigger:
      - platform: template
        value_template: "{{ states.light.master.attributes.brightness }}"
    action:
      - service: input_slider.select_value
        data_template:
          entity_id: input_slider.brightness_master
          value: "{{ trigger.to_state.attributes.brightness | int / 2.55 | round(0) }}"

Doesn’t like the template/value_template in the trigger here.

2

Could you create a sensor from your value template and then use the state trigger on that new sensor? Example but don’t cut and paste, check my work first. LOL

-  platform: template
     mbr_brightness:
       value_template: "{{ states.light.master.attributes.brightness }}"

then

- alias: "Brightness - Master Bedroom Brightness Change (Device > Slider)"
    trigger:
      - platform: state
        entity_id: sensor.mbr_brightness
    action:
      - service: input_slider.select_value
        data_template:
          entity_id: input_slider.brightness_master
          value: "{{ trigger.to_state.attributes.brightness | int / 2.55 | round(0) }}"