Flowing line sensors always for values 3, although left sensors and right sensors are not on white?


#1

I have an idea of programming for free fall avoidance with flowing line sensors but have not thought of a way yet
So I used the ultrasonic sensor, and it worked
Then I discovered a video using flowing line sensors

Why in video: flowing line sensors always for values 3, although left sensors and right sensors are not on white
Normal: flowing line sensors for values 3 when left sensors and right sensors is on white color (Both LEDs light up)
But in the video …